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ACRosalino

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* what is the best way to use just one Baader-U 2" filter on the various lenses? Is there an "easy filter swap" solution, for a reasonable price?

Such solution should also allow to easily shoot Visual-->UV-->IR frames, using various other filters, without disturbing the camera pointing and focusing...

 

* how can I use a lens shade/hood on these lenses? I am not sure how to fit one, when using 2"/M48 astronomy UV filter, mounted on some kind of adapter, so that it can fit on a 52mm filter ring on the lenses - but I am sure someone here has found a working solution, also for this?

 

 

Hi António,

 

I like your lens selection and have all of them myself. My favourite is the 80mm EL-Nikkor old metal version.

 

I relocated my Baader U filter glass into a pair of 48-52mm step rings to get a 52mm filter cell with threads both at front and rear end.

There are other ways to do that, or you could just place such up and down-rings on the Baader 2" filter cell.

https://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=step%20ring%2048%2052&rt=nc&LH_PrefLoc=5&_trksid=p2045573.m1684

 

I do a lot of filter swapping during my photo sessions and have a solution that works well for me.

When possible I adapt the filter thread size on the lens to a 52mm thread with suitable step-rings.

 

For an "easy filter swap" solution I use a Xume lens adapter on the lens and matching Xume filter adapters on each filter.

https://www.ebay.com...ter+52&_sacat=0

If your setup is sturdy enough the cameras pointing direction will not be disturbed when swapping filters.

For VIS-NIR I do the same with 77mm adapters om my normal Canon EOS-lenses and big filters. It saves much time when swapping filters.

 

Your EL-Nikkor lenses has an on odd filter thread, 34.5mm x 0.5mm and the fitting step rings are not China-cheap:

https://www.ebay.com...aon-q:rk:2:pf:0

As an alternative you could permanently glue a 34mm - 52mm step ring on the lens or try to place some suitably thin spacer materials between the 34mm and 34.5mm threads.

That worked well for me when I was waiting for the proper ring to arrive.

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Thanks for the help, Ulf: I have ordered two of those Russian made M39.5x0.5M-->M52x0.75F adapters, which will kind of standardize my EL-Nikkors

(I will deal with the Steinheils later - I am not sure yet which filter threads they use, but that should be easier to deal with).

 

If I understood you correctly, the 2" M48 Baader-U will work fine with the common and cheap M48-M52 step up adapters, which I believe use 52mmx0.75mm threads? If that is the case, I will likely sandwich it between 2 of those adapters, just like you did.

 

The Xume magnetic adapters seem to be what I am looking for: so, I will need one magnetic adapter for each one of my lenses... and just a single magnetic adapter for the Baader-U (for its 52mmx0.75mm adapter, really) - do I get it right?

 

Also, since the exposed/front side of the Baader-U will also have been adapted to M52mmx0.75mm, I suppose will be able to use a lens shade/hood on this adapter?

And maybe even some kind of lens cover, which fits on top of that shade/hood?

 

Making a "normal" lens out of those EL-Nikkors is more work than I had anticipated... and all these different threads/pitches are a true nightmare!

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(I will deal with the Steinheils later - I am not sure yet which filter threads they use, but that should be easier to deal with).

My Steinheil Cassar-S 50mm has a 40.5mm filter thread You'll need a 40.5-52mm step up ring.

 

If I understood you correctly, the 2" M48 Baader-U will work fine with the common and cheap M48-M52 step up adapters, which I believe use 52mmx0.75mm threads? If that is the case, I will likely sandwich it between 2 of those adapters, just like you did.

 

Also, since the exposed/front side of the Baader-U will also have been adapted to M52mmx0.75mm, I suppose will be able to use a lens shade/hood on this adapter?

And maybe even some kind of lens cover, which fits on top of that shade/hood?

 

For the Baader U filter cell you can use cheap step-up and step-down rings 48-52 and 52-48.

I thought that combination was too long and relocated the filter glass from the thin-walled Baader filter cell.

I do not remember exactly how and cannot check as the parts are under the edge label I added.

I think I used step-up and step-down rings 48-52 and 52-48 plus the M48 retaining ring from the Baader filter cell.

 

It will be possible to use a m52 threaded lens shade there.

 

The Xume magnetic adapters seem to be what I am looking for: so, I will need one magnetic adapter for each one of my lenses... and just a single magnetic adapter for the Baader-U (for its 52mmx0.75mm adapter, really) - do I get it right?

 

For a full spectrum modified camera you'll need at least two filters and filter adapters. One for UV, like the Baader U and one to restore the filtering of IR that will be removed during the conversion of the camera to full spectrum.

Then you will be able to take normal VIS images too.

I would recommend a BG38 or BG40, 2mm Ø52mm for that.

 

For IR you can use different types of IR-pass filters, depending on what you are aiming for.

Above 760nm you get monochrome images as the three colour channels have very similar sensitivity.

 

If you like to experiment with other types of filter-stacks with UV as a part of the recorded spectrum I would recommend a S8612, 2mm thick filter.

 

Making a "normal" lens out of those EL-Nikkors is more work than I had anticipated... and all these different threads/pitches are a true nightmare!

You need some way to adjust the focus too:

http://www.ultraviol...dpost__p__17389

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Thank you, Ulf: I just ordered a couple of 40,5mm to 52mm step up adapters, in order to also "standardize" the 50mm Cassar-S and Cassaron filter threads.

And I also ordered the 52mm-48mm and 48mm-52mm adapters, in order to sandwich the 2" Baader-U, when I finally find the courage to purchase one :-)

Also selected a few M42-M42 helicoid focusers of various sizes, in order to be able to focus the 2 EL-Nikkors: I think that, step by step, the pieces of the puzzle are beginning to make sense!

 

Regarding visual and IR use of the full spectrum Canon EOS-M, my first idea was to continue to use Baader filters... maybe because I have been using those for astro-imaging, with decent results:

 

* they have a 2" UV/IR Cut filter, blocking UV below 400nm and IR above 680nm - would that be appropriate for visual imaging?

* they also have a 2" IR-Pass-Filter, 685nm - would that be appropriate for IR imaging?

 

In any case, I will try to learn more about the filters you have mentioned (BG38, BG40, S8612), especially since the Baaders are not exactly cheap.

 

 

Also thanking you for the content link, John: it is good to know there is an alternative to the magnetic adapters - only it was not clear for me if those Nikon extension rings K will work only with Nikon lenses... or if they can be adapted to any lens with a standard 52mm filter thread?

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Regarding visual and IR use of the full spectrum Canon EOS-M, my first idea was to continue to use Baader filters... maybe because I have been using those for astro-imaging, with decent results:

 

* they have a 2" UV/IR Cut filter, blocking UV below 400nm and IR above 680nm - would that be appropriate for visual imaging?

* they also have a 2" IR-Pass-Filter, 685nm - would that be appropriate for IR imaging?

 

In any case, I will try to learn more about the filters you have mentioned (BG38, BG40, S8612), especially since the Baaders are not exactly cheap.

 

 

I'm sure the Baader filters are of excellent optical quality. The UV/IR cut filter however lack one thing. It do not restore the characteristic of the cameras original blue-green colour-shaping filter that is removed during conversion.

Of the two filters I removed when I converted my EOS 60D the BG-filter appears to be the most important to replace for a decent colour balance for VIS images.

http://www.ultraviol...dpost__p__17625

 

One of our members, Cadmium has a company that is making and selling specialised filters like BG38, BG40, S8612 and many other.

I have always been pleased with the filters I bought from him.

https://www.ebay.com...=p2047675.l2562

 

For IR -pass filters I have used filters from Zomei.

https://www.ebay.com...0&_nkw=zomei+IR

They are a Chinese company with reasonably good quality of their filters and have a range of filters for IR-pass.

So far I have not seen any problem with those filters and have both 77mm and 52mm versions.

The 77mm versions fitting my wide angle EOS-lenses, for NIR landscape photography.

 

You might want to explore both pure NIR (>780nm) and cut on wavelengths closer to VIS getting some faint colour variations due to the bayer channel sensitivity variations near at 680-780nm

A filter for simulation of the old Kodak AIR IR- colour film might also be interesting. Then you need an orange filter.

 

I have been playing around with most normal sharp cut filters filters for IR imagery and if I should select a few of them I would get these:

one with a cut-on at 530nm - 550nm for AIR

one with a cut-on at 590nm for Goldie images, search for "Goldie IR image" on the net.

one with a cut-on at 650nm - 700nm for almost NIR with colours

one with a cut-on at 780nm - 850nm for pure NIR, monochrome

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For IR -pass filters I have used filters from Zomei.

https://www.ebay.com...0&_nkw=zomei+IR

 

I think the key phrase there is "From China", and certainly they are, and without any good data for inclusion in other stacks or such.

not a good idea, certainly NOT Schott or Hoya glass.

Good science starts with good data.

 

"I have been playing around with most normal sharp cut filters filters for IR imagery and if I should select a few of them I would get these"

Please show us how these are any sharper cutoff than Schott.

You even have a USB, right? Do you have comparisons?

I await your comparisons.

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I think the key phrase there is "From China", and certainly they are, and without any good data for inclusion in other stacks or such.

not a good idea, certainly NOT Schott or Hoya glass.

Good science starts with good data.

 

I strongly agree that "Good science starts with good data"!!

 

But not all from China must be bad by default.

I do not have any Schott or Hoya filter for NIR for the direct comparison.

If you like to send me some suitable glass for testing, I'll happily do that comparison, but I do not want to buy any more IR-filters just now as I am satisfied with the Zomei IR-filters for now.

 

When I compared the cutoff steepness for the Zomei IR-filters with all my VIS B+W filters, 022, 040, 041, 090, 091, with cutoffs furter into VIS, (based on Schott-glass), the Zomei filter's cutoff and IR-transmission behave very similar, but with different cutoff wavelengths.

 

I am quite experienced in looking for surface flatness, dimples and striations in optical components and have inspected the Zomei filters very carefully without finding any flaws visible to the naked eye.

The images they produce are also sharp. The wavelength designations are likely not that well correlated to the cutoff point and for real scientific work it should be verified with a spectrometer.

 

IMHO Zomei IR-filters hold a reasonable quality level and work well enough for non scientific photography, even if they are produced in China.

 

When you compare cutoff steepness the American Tiffen filters like the proper filter for AIR, Tiffen 12 are less steep than the glass from Schott.

It might be intentional.

I do not think this steeness is very important for our type of photography as the final false colour result is affected very much by the post processing.

 

"I have been playing around with most normal sharp cut filters filters for IR imagery and if I should select a few of them I would get these"

Please show us how these are any sharper cutoff than Schott.

You even have a USB, right? Do you have comparisons?

I await your comparisons.

 

Sorry I do not understand what I shall compare here.

I just gave a set of suitable cutoff wavelengths for what I think would be usable for different types of IR-photo.

My first choice would be Schott glass based filters

 

Sometimes you can find filters with such cutoffs made for quality brands like Schneider (B+W).

They use Schott glass, but not all types are available anymore.

The B+W 023 530nm is not produced anymore and if that cutoff is desired it must be obtained elsewhere.

 

Sometimes the best source for filters are good specialist companies like UVIROptics. ;-)

 

For 680nm and 850nm filters Zomei works well for me.

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Sometimes the best source for filters are good specialist companies like UVIROptics. ;-)

 

And sometimes the specialist company is UVROptics. ;-)

 

Antonio,

In contrast to the BaaderU, perhaps getting a UV-bandpass filter that is optimized for the UVA wavelengths, including the photon-dense range of 370-400nm might be a better bet. For that the new SEU Gen3 from UVROptics is the only game in town. The BaaderU blocks much of the long-wavelength UV, because it is based upon the Schott UG11 type of glass. The SEU Gen3 manages the UV wavelengths through two dichroic coated Boroflot glass elements. The Gen3 costs $100.00 less than the BaaderU, is a true 52mm, not 48mm, and comes with a 52mm lens hood and two anodized aluminum stacking caps. We just finalized the Gen3 last week and have found it to be faster than the Gen2, which was faster than the BaaderU.

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I confess I am still confused as to which is the best filter to restore "normal" colors on a full spectrum camera: from what I have read here, it seems results will vary, depending on each camera's CMOS sensor and the (now removed) filter package that was factory installed?

 

These B38, B40, S8612 or Baader UV/IR are relatively expensive (around 100 Euro) and, if best results cannot be guarantee without experimentation first with a few of these filters - maybe the wisest solution will be to just get another camera body and use it, unmodified? After all, another EOS-M costs pretty much the same as a single Baader UV/IR filter!

 

Of course, if you are shooting with an expensive full spectrum camera, it is another story...

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I confess I am still confused as to which is the best filter to restore "normal" colors on a full spectrum camera: from what I have read here, it seems results will vary, depending on each camera's CMOS sensor and the (now removed) filter package that was factory installed?

Results for which is the best do, in fact, vary depending on the model of full spectrum camera. However the Baader UV/IR cut filter is different from the Schott glasses, in that it does not attempt to reduce any of the red. The other ones reduce red to varying degrees.

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Thank you, Reed, for the important info on the Baader-U alternative - timing is good, for I have not yet pulled the trigger on any of the various UV filter alternatives :-)

 

Now, I have read here time and again that the Baader-U is the "reference" filter to get for UV imaging... and I have had consistently good experience with various Baader filters for astronomy.

Are there any real images produced with the new filter, already - eventually, a side-by-side analysis ref. other more established (older) UV filters?

 

PS: price of the SEU Gen3 seems to be more affordable than the Baader, yes - on the other hand, once it crosses the Atlantic and is subject to duties & taxes, I suspect prices will be on the same level...

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Antonio,

 

Andrea did a 12 part series of tests comparing the SEU Gen2 (not Gen3) to the BaaderU and the KolariU. See http://www.ultraviol...+%2Bseu+%2Bgen2

 

Very complete testing with lots of images! The landscapes in #5 are very nice.

 

So, that was the SEU Gen2. The Gen3 is faster yet, but neither of the two samples I sent for spectrophotometer testing by Ulf have arrived...yet. My fault, lessons learned about Swedish Postal Services. I did a preliminary Spectrophotometer test on my Hitachi U1500, but I lack the precise equipment and skills that Ulf has at hand for a detailed analysis.

 

One advantage of the Gen2 and Gen3 over the BaaderU is the NIR blocking.

 

I have some UV/IR 650 cut filters in 49mm that I step up to 52mm. Pretty standard dichroic filters, 1.0mm thick. I haven't put them on the website yet, but $37.50 USD will be the price.

http://uvroptics.com/images/Our-Hot-Mirror-Graph-WB900px.jpg

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I want to make it clear that I have no direct affiliation to either of the two specialist companies.

UVIROptics (Steve (Cadmium)) or UVROptics (Reed Curry).

 

I have bought more than ten different filters from Steve and one SEU2 from Reed.

My passion is measurement technology and I have done the measurements just for the pleasure of doing it.

I have had many interesting technical friendly discussions about filters and filter design with both Steve and Reed

 

In my opinion both UVIROptics and UVROptics are very qualified companies in their special areas.

 

lUVIROptics specializes in producing high quality ionic absortion-filters.

UVROptics main filter the SEU-x line is a customised dichroic filter type just as Baader U.

 

Both types of filters has their pros and cons complementing each other.

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I confess I am still confused as to which is the best filter to restore "normal" colors on a full spectrum camera: from what I have read here, it seems results will vary, depending on each camera's CMOS sensor and the (now removed) filter package that was factory installed?

 

For restoring the general colour balance BG38 or BG40 are the best alternatives as they do not cut away too much of the red spectrum.

UV/IR-cut filters do not balance the colours well.

 

The difference between BG38 and BG40 is quite well canceled during the normal custom white balance and is not that important.

 

The S8612 is by far the best filter for eliminating IR-leaks when used in combination with many other UV-pass filters like UG1, UG11, U-340, U-360, but not suitable for VIS as it cut too much red.

The UG1, UG11, U-340, U-360 all have a secondary transmission peak the NIR that must be eliminated for a pure UV-transmission.

The secondary peak will otherwise overpower all UV-light.

 

I use my S8612, 2mm as the standard IR-canceling filter when experimenting with different filter stacks.

With that thickness I have never had any problems with IR-leaks.

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You might want to explore both pure NIR (>780nm) and cut on wavelengths closer to VIS getting some faint colour variations due to the bayer channel sensitivity variations near at 680-780nm. A filter for simulation of the old Kodak AIR IR- colour film might also be interesting. Then you need an orange filter.

 

I have been playing around with most normal sharp cut filters filters for IR imagery and if I should select a few of them I would get these:

one with a cut-on at 530nm - 550nm for AIR

one with a cut-on at 590nm for Goldie images, search for "Goldie IR image" on the net.

one with a cut-on at 650nm - 700nm for almost NIR with colours

one with a cut-on at 780nm - 850nm for pure NIR, monochrome

 

Thanks for the very practical filter recommendations for IR :-)

 

I see that Zomei have at least the following IR filters: 680nm, 720nm, 760nm, 850nm and 950nm

It seems the 680nm and the 850nm would be a good fit for colored NIR and mono NIR, respectively; as to the 950nm, will it "show" anything more/different, compared to the 850nm... or is it kind of redundant?

 

Besides those 2 above, could you recommend any specific filters for the "Kodak AIR" and "Goldie IR" effects, in the same price range?

As far as I can tell, Zomei does not sell any covering those wavelengths... and a quick eBay search mainly returned "variable wavelength" IR filters (are they any good)?

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There is a lot of content on this site, here is a very good filter quick release filter attachment method from several years back.

 

http://www.ultraviol...27-inside-tips/

 

B)

 

Well, I revisited that link and the great info it contains - thank you, Birna - and, finally realizing that such system can be used with any lens with 52mm filter threads, I have just ordered my first set of Nikon Extension K rings.

 

It seems to be cheaper than the "magnetic" solution for quick filter swapping and, I must say, those rather old K rings are also a better match for the "vintage" lenses (EL-Nikkors, Steinheils, etc.) I have been collecting for UV use :)

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Thanks for the very practical filter recommendations for IR :-)

 

I see that Zomei have at least the following IR filters: 680nm, 720nm, 760nm, 850nm and 950nm

It seems the 680nm and the 850nm would be a good fit for colored NIR and mono NIR, respectively; as to the 950nm, will it "show" anything more/different, compared to the 850nm... or is it kind of redundant?

 

Besides those 2 above, could you recommend any specific filters for the "Kodak AIR" and "Goldie IR" effects, in the same price range?

As far as I can tell, Zomei does not sell any covering those wavelengths... and a quick eBay search mainly returned "variable wavelength" IR filters (are they any good)?

 

There is not a big difference between images made from 850nm- and 950nm-filters.

However the 950nm-filter transmit much less usable photons, making the exposure-time much longer.

I never use my Zomei 950nm anymore.

A RG1000, 1mm specialist filter thick will improve exposure times and work better than the Zomei 950nm filter.

I expect without ever having used one of those filters that the images will often look rather similar.

 

Correct filter for AIR is the Tiffen 12 with a cut on at ca 530nm.

The OG530 based filters from B+W, (model 023) are not produced any more.

You might get a secondhand with some luck.

 

I want Ø77mm to fit my EOS-lenses for this kind of landscape photography and have never found a 023 Ø77mm.

I have successfully used the B+W 040 (OG550, 550nm) for both AIR and Goldie instead.

The B+W 041 (OG570, 570nm) is slightly better for Goldie, but not much.

The difference is fixed in the final image processing by a small hue shift.

 

I suggest that you, to begin with, just get a B+W 040 in a size that suits your needs.

https://www.ebay.com/sch/Filters/15216/i.html?_from=R40&_nkw=B%2BW+040

 

Nikon also have very nice Hoya-glass based filters that can be found at eBay.

The Nikon O56 560nm could be an alternative. (not Ø77mm?)

https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=Nikon+O56&_sacat=0

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I have just received my 2nd EL-Nikkor (80mm f/5.6 "metallic") and, together with it as a bonus, I also received a (newer version) EL-Nikkor 50mm F/4.

While this 50mm lens seems to be in great overall condition, I am puzzled by its aperture blades pattern: when fully opened at f/4, instead of the "normal" circular lens opening, the blades remain partially visible, turning the lens opening into a well formed octagon!

I do not know if this is normal for this particular lens or if this indicate some kind of aperture blades problem... maybe someone here has as similar lens and would kindly provide some feedback? Thanks! :unsure:

post-228-0-75480100-1548441534.jpg

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Yes, that's what I think, too... just do not know how easy it is (or not) to open the lens and attempt to adjust something :(
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The normal restoration filter can be tricky and camera dependant. I would say if you own a baader uv/ir filter, than test that first. It may work or may work if you set the wb to tungsten. If it doesn't than a bg40 will work.

 

As for the octagon, take some photos and see if you like it. There are some lenses that have a hard square and others with odd triangle. They produce interesting bokeh balls that some people like.

 

The important thing is to start having fun.

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  • 1 month later...
Still tempted by full frame, mirrorless camera alternatives, for full spectrum conversion... Any thoughts on the Sony A7S? Its excellent sensor sensitivity in low light conditions should be a big advantage for UV, right? 12MP seems a bit low, for today's standards, but since I will be using it mostly with 'vintage' glass, that won't be a limiting factor, I guess...
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From what I understand (read somewhere here in a sticky I think) the Sony's have some internal LED that interferes with the image.

I have also seen on Lifepixels site that they can remove the LED (or was it Kolari Vision?)

 

Either way, best check it out before you splurge the cash!

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