IR Chome reds with sd Quattro

[GaryR]

I haven't used my Kolari Vision IR Chrome filter in a while, and decided to try it out on my newly acquired Sigma sd Quattro H. Instead of the usual orange tones, the sdQh seems to produce a vivid range of magenta/reds SOOC. Not much greenery this time of year, but here are a few test shots.

 

Snowdrops "Cine" color mode

 

Snowdrops "Standard" color mode

 

Steet scene "Standard" color mode

[dabateman]

That cine color mode looks good.

I am resisting buying an SDQH, as I can't afford one and I know I will not use it much. But that does look good.

Its also the best BW camera I have played with.

[GaryR]

David,

Yes, BW and monochrome IR is excellent. I haven't tried UV yet, but I expect to be limited to monochrome, which is fine with me.

[colinbm]

Gary, Thanks for posting these good examples from the SDQH, I have the SDQ to get fired up soon as I get flashes & LED lighting finished.

Dave the SDQ is a lot more affordable then the H & basically the same, just not the larger sensor.

[Cadmium]

Gary, you had your Sigma sd Quattro H converted to full spectrum somewhere?

[dabateman]

Gary, you had your Sigma sd Quattro H converted to full spectrum somewhere?

Anyone can. It just has a pop in UV/IR blocking filter. You can make it full spectrum at will.

If your curious about one you can rent from Lens Rentals.

https://www.lensrentals.com/rent/sigma-sd-quattro-mirrorless-w-30mm-f1.4-dc-hsm-art

 

You can also download the user manual from that link to see how to pop in and out the filter.

[Cadmium]

Thanks David.

 

Gary, Are you using the filter on the front of a lens?

What lens are you using?

[colinbm]

As simple as A B C....

https://www.sigma-im...tim-shoebridge/

 

PS. this is Sigma SD Quattro.

The SD Quattro H is identical, except with a slightly larger sensor & a much higher price.

Col

[GaryR]

As mentioned, the dust protector/IR-cut filter simply pops out. That's a $500 Cdn savings for me, and no conversion worries. There's no way I'd attempt to pop the dust protector out "in the field" with tweezers, while juggling a lens. Mine is safely stored in a B+W filter box, and will use an external hot mirror, for normal photography.

 

For this set, I used a Sigma 70mm f/2.8 DG lens, which has a surprisingly small 49mm filter thread. A step-up ring was used to adapt my 52mm IR Chrome filter.

 

Yes, the APS-H model is essentially the same as the APS-C model, but a limited choice of lenses, if you want full "H" resolution without vignetting. Fortunately, the "H" model does have an APS-C crop function (in menu), which gives you a wider selection of "DC" and legacy lenses. If you're not interested in expensive "DG" lenses, the regular APS-C sdQ is a more economical choice.

[Cadmium]

Thanks Gary. :-)

Do you have any B-410?

[GaryR]

Thanks Steve, but no I don't have a B-410. On the Quattro, I've discovered that a single kolari or Spencers Hot mirror filter, both seem to leak some IR (purple cast on green leaves). The best visible color so far, is with a Spencers and generic dichroic hot mirror stack...greens are green and blacks are black, instead of slightly purple. Matching the colors that you get with the stock IR-cut filter is tricky.

[colinbm]

I am curious about the ' Spencers Hot mirror ' Gary ?

[Cadmium]

Gary, I asked about the B-410 because it works just like the Kolari, especially when stacked with KG3.

As far as visual, I can't say because I have no experience with that or any Sigma. I think you have experience with other Sigma models, correct? What filters have you used on other Sigmas that work best for those models?

I don't know what those two mentioned are made of, other than my guess is probably some close equivalent to BG40.

I prefer BG38 for my cameras, but BG40 works well, just slightly more blue. I don't like using S8612 for visual,

Someone with a newer full spectrum Fuji used for forensics tried these, S8612, BG40, BG38, and found the S8612 to be spot on the money for visual, which surprised me completely, looked perfect.

S8612 does cut off more red/IR, so if your cast is from IR like you think, then the S8612 would remove more red/IR than BG40.

Here is my observation with visual filters on my Nikon cameras:

BLUER < S8612/BG39 - BG40 - BG38 - Baader UV/IR-Cut > REDDER

[GaryR]

Colin,

I took this comparison shot some time ago, when I had an APS-C Quattro.

 

I like the quality of slim Kolari filter ring, whereas the Spencers is very lightweight ring, with a silver label.

https://www.spencers...&Category_ID=11

 

Steve,

The stock sdQH hot mirror is cyan, like the Kolari and Spencers, but also has a dichroic coating.

 

A Kolari, stacked with Tiffen hot mirror worked well on my SD15, but not as well on the sdQ. The cheap generic 52mm dichroic hot mirror that I have, works surprising well with the 70mm lens, but I also need a 77mm version for my other Sigma lens. 77mm filters are quite expensive, so I'll have to be sure it works, before considering that option. An external stack would be ideal, but I could just install the stock sdQH mirror if need be.

 

When the weather warms up, I'm going do an outdoor color test with the sdQ IR-cut filter installed, and with external filters. Comparison shots should tell me how close, or far off I am to the original Sigma colors.

 

For now, I'm mainly shooting monochrome 720nm

[colinbm]

Thanks Gary

I need to get some SDQ dust protector frames cut....somewhere......& try internal filters...?

[dabateman]

For my SD14, the BW 486 worked perfectly to regain visible. But in the ones I have I now have tested quite a variation in IR leak. My original 58mm BW486 has low IR leakage, but a newer 58mm BW486 I bought 3 years ago has quite alot. So they maybe less efficient now. I now use it with a cheap LP720 to Isolate the 690 to 750ish area.

When I rented an SDQ, my original BW486 worked well.

But I didn't test all my other filters.

The Sigma seem to like a hard cut closer to end of 600nm. The BG glass cuts off too much red.

[colinbm]

From my understanding the Sigma Hot Mirror has a steep cut on & off at 420 to 680nm.

[dabateman]

From my understanding the Sigma Hot Mirror has a steep cut on & off at 420 to 680nm.

 

This was the post were I included my scans of the Sigma Sd14, Sd15 anfd my original BW486 filter:

https://www.ultravioletphotography.com/content/index.php/topic/2665-sigma-dust-block-filters-bw486-and-my-venus-2-spectra/page__hl__%2Bsigma+%2Bspectra__fromsearch__1

 

Sadly I don't have access to a spectrometer now or when I rented the SDQ.

 

 

[GaryR]

Thanks Gary

I need to get some SDQ dust protector frames cut....somewhere......& try internal filters...?

 

Yes, the IR-cut filter is a difficult part to find. I ordered the last one in stock, from our sole Canadian distributor Gentec. Sigma USA will not ship to Canada. As far as the frame itself, I came across a 3D print file, for the sdQ filter frame. I haven't had any need to try it, but there are plenty of 3D printing services available if you want to give it a shot. I'm not sure if the original frame is made of nylon or a hard plastic ??

 

https://www.thingiverse.com/thing:3713556

[GaryR]

From my understanding the Sigma Hot Mirror has a steep cut on & off at 420 to 680nm.

 

Thanks Colin,

That's good to know !

[colinbm]

Something odd with that link Gary....?

The hot mirror frame is a hard plastic as the glass is sub 1mm & fragile.

I think I need to find someone to cut the frame in carbon fibre sheet say 1mm ?

Then the glass is a slight D shape ?

[GaryR]

Colin,

Not sure why the link doesn't work when you click on it. Copy and paste does work.

Yes, that slightly flattened edge of the glass, doesn't make it any easier.

That's why I'm sticking with external filters.

[colinbm]

Got it thanks Gary

Good to have this file, I'll try & find someone to make me a few...

[dabateman]

Colin,

Not sure why the link doesn't work when you click on it. Copy and paste does work.

Yes, that slightly flattened edge of the glass, doesn't make it any easier.

That's why I'm sticking with external filters.

 

Had a look at it. You are correct, you need to copy and paste the link. The design looks slightly different. I think he may have made this to accept 37mm diameter glass without the d cut edge. So just getting custom ordered 37mm glass might work.

Thank you for the files.

[Andrea B.]

This might be slightly off topic.

I was particularly interested in the above mention of using 3D printing for a camera part because I've wondered whether 3D printing might be useful for making hard to find filter-to-lens fittings? For example, I have a really old Asahi 50mm lens (which is fairly good for UV) which has no filter threads. But I can see that a cap-like fitting which holds a filter in the center would work if only I could get that cap-like part made to fit over the indentations on the front part of the lens.