Question about MaxMax complete solutions

[AHawkins]

I am looking into using passive UV photography for a project at work. I have a background is in physics, but little experience in photography. I am trying to find a solution that is digital, low cost, high resolution and capabale being semi-mass produced (dozens to hundreds). The cheapest lenses I could find for F-mount cameras were over $5,000.

 

However I came across some apparently complete solutions from maxmax.com. Does anyone know if these are really the "full package" and if they are any good? I provided links for the two I am most interested in (i.e. cheapest).

 

http://www.maxmax.com/shopper/product/15551-xnitecanon1000duv-canon-1000d-10-0-megapixel-uv-only-camera-black-with-18-55mm-lens

 

http://www.maxmax.com/shopper/product/15556-xnitenikond3200uv-nikon-d3200-24-2-mega-pixel-digital-uv-visible-ir-enabled-slr-camera

[Andrea B.]

To properly answer your question it is necessary to know what subjects you plan to photograph and how you plan to illuminate the subject. But I will take a stab at it anyway.

 

The lenses offered by MaxMax with the 'full package' solutions are not UV-dedicated lenses. They are just ordinary kit lenses. However, with enough good UV illumination and a long enough exposure, the kit lenses will work to record reflected UV in the higher bandwidth range. I can't be sure of the exact transmission range of these lenses, but I would guess it is probably between 370-400 nm ?? Perhaps if you call MaxMax and talk to Dan, then he might be able to provide you with a better estimate of the UV range you could expect with these lenses when used with good UV illumination.

 

If what you are looking to photograph in UV reflects under 370 nm or is moving, then these lenses will not work for you.

 

The cameras offered by MaxMax both would work for UV because they have been converted. But an important consideration is whether the internal UV-pass filter offered in the MaxMax kit strongly blocks Infrared to between OD3 - OD4 or whether an additional IR-blocker is needed for the lens. Infrared contamination is the bane of UV photography and must be blocked. Adding an additional IR-blocker is not too expensive.

 

*******

 

As a sanity check on prices, if you bought camera, conversion and filter separately, then the approximate cost might be about $1000. But the UV-pass filtration would be external (on the lens) not internal.

 

Nikon D3300 + 18-55 Kit Lens: $550.00 (approx.)

Conversion to Full Spec: $275.00 (ask for a discount if converting multiple cameras.)

UV-pass Filter Stack: $180.00 (approx.)

 

Note that UV illumination in the form of a Xenon lamp or modifiec Xenon flash is not factored into this estimate.

[AHawkins]

The subjects will be live humans, so I doubt we will be using any illumination. Also multiple images are required in succession so the ability to take multiple questions rapidly (1+ FPS) is desired. A few megapixels are also required.

 

I found a cheaper (~$1500) C-mount lens (http://www.edmundoptics.com/imaging-lenses/fixed-focal-length-lenses/uv-fixed-focal-length-lenses/57542/) but I cannot find any C-mount cameras that meet the resolution and frame rate that I require.

 

Does anyone know of any solutions or combination of solutions that might fit my requirements?

[Andrea B.]

You might need some kind of extra illumination for UV photography if you hope to have short exposures.

 

Outdoors, in sunlight there is only 3-4% UV on a bright, sunny, cloudless summer day between 10am - 2pm at certain elevations. So you can see the problem if it is not summer or if it is not mid-day or if you are at a higher elevation or if the day is cloudy. :(

 

A camera with really good high ISO capability (signal boost) will be needed to ensure shorter exposure times. That puts you into Sony or Nikon territory. I'd go to the D5500 or D7200 for better high ISO. The Sony NEX bodies would also be good.

 

Any converted Canon, Olympus or Panasonic would also work, but they do tend to be noisier at high ISOs. So you would have to make a decision about what image quality you are looking for.

 

I think you could get that 1 FPS or better with that D3300 if you set the ISO to 800 or above in good UV light using the kit lens. But will you always be able to shoot outdoors under aforementioned conditions?

[rfcurry]

If you will not be using any additional illumination, then you do not need a lens that is good to 230nm, because solar UV doesn't get below UVB. There are plenty of used lenses that will get you down to the 320nm that is the bottom for many standard camera sensors. The Cassar, Cassarit, and similar triplets can manage that (see the lens sticky).

 

A C-mount lens will give you vignetting on most common sensor sizes. You can always do a bit of cropping, of course. The Micro 4/3 mount in the Panasonic Lumix cameras will take the C-mount lenses with an adapter, and the sensor size is your best fit there as well. With a decent old lens, you will be able to record UV video with such a camera on a sunny day, so 1 FPS is not an issue.

[AHawkins]

Since we will need a large quantity, I am trying to avoid used or converted hardware. Does anyone foresee see any issues with the following combination?

 

Camera $475.00 http://www.maxmax.com/shopper/product/15717-usb-ind-5m-usb-industrial-monochrome-5-0-megapixel-camera

Lens $1,495.00 http://www.edmundoptics.com/imaging-lenses/fixed-focal-length-lenses/uv-fixed-focal-length-lenses/57542/

Filter 1 $34.50 http://www.edmundoptics.com/optics/optical-filters/bandpass-filters/colored-glass-bandpass-filters/48637/

Filter 2 $34.50 http://www.edmundoptics.com/optics/optical-filters/bandpass-filters/colored-glass-bandpass-filters/46047/

[Andrea B.]

How exactly does that camera work for focusing when attached to the laptop? Can the attached laptops be easily used outdoors? If this setup forces indoor work, then you are back to needing extra UV illumination.

 

Is a 5 megapixel, black and white photo high enough resolution for you?

 

I'm not sure about the filter stack. I don't think that BG39 is enough supression for a UG1? But that is easy enough to look up from our member Cadmium's graphs. I'll find one and put the link here: http://www.ultravioletphotography.com/content/index.php/topic/1313-filter-transmission-charts/page__view__findpost__p__7838

 

Also, note that this kind of industrial lens is meant to be used with narrowband UV filtration due to the uncorrected chromatic aberration. This may show up as edge "blur" and/or false colour fringing when used with wideband illumination (sunlight, for example) and filters like the UG-1.

 

Edmund Optics writes:

These lenses are not corrected for chromatic aberration, and require refocusing when using an illumination source with a spectral bandwidth greater than 10nm. A monochromatic light source and narrow bandpass filter are recommended to improve the overall performance of the lens.

[rfcurry]

The filter selection is off. Here is what you get with your choice:

http://uvroptics.com/images/3and3.jpg

Paying all that for a lens, you should, IMO, get a better filter. The UG1 in 1.0mm and the BG39 in 1.0mm will give you a 63.3% peak transmission, not 28%, and would still have a >OD3 IR peak.

 

The 25mm lens probably has a plethora of elements, each group of which will reduce the total transmission. Edmunds is assuming, IMO, that you will have supplementary lighting. You would be better off, again IMO, with a 50mm lens that will use fewer elements/groups.

[Andrea B.]

Thanks for the chart Reed. The BG-39 will supress enough IR if it is thick enough. A 1-mm BG-39 is not thick enough. But thicker BG-39 is easily available on Ebay from the seller uviroptics.

 

And I note that non-stacked UV-pass filters are available from the seller uvroptics.com and also from Edmund Optics.

 

**********

 

The problem in judging the potential of any of the setups that Mr. Hawkins is asking about is that most of us have no experience with them. Most of us here shoot full spectrum converted DSLR or mirrorless cameras with either UV-dedicated or UV-capable lenses using an external filter or filter stack. I don't know of anyone here who uses a CCD camera for general UV imaging. And most of us do not use modern kit lenses, although many of us have experimented enough with them to know that you can record near-UV with them under enough UV light and with long enough exposure. Also most of us who have used industrial uncorrected UV-pass lenses have found the image quality somewhat lacking under wide illumination.

 

*********

 

How about investing in one really good, professional UV photography kit and letting everyone take turns with it? At least that way you would ensure a good image quality and might actually be able to shoot at a higher FPS rate ??

[Cadmium]

You want 25mm diameter?

I would recommend U-360 instead of UG1, U-360 is a bit more efficient than UG1, but either will work about the same.

I would not use BG39, it has no redeeming advantage over S8612, and only cuts off more UV.

You can even use BG40 instead (but twice the thickness).

As far as thickness, your thicknesses are thicker than need be. This will require longer exposure time.

Using a UG1/U-360 stack, to play it safe I would try this stack first: U-360 (or UG1) 2mm + S8612 2mm.

 

Here is a nice stack:

[Cadmium]

Here is an example showing why S8612 is best to use instead of BG39.

At the same thickness S8612 and BG39 have the same transmission curve for IR suppression.

However, S8612 has deeper and stronger UV transmission.

So for UV stacking it is preferable to use use S8612 instead of BG39, because it will give the stack deeper UV transmission, and also stronger peak amplitude,

all of which translate into shorter exposure time and also more potential UV false color palette.

[AHawkins]

How do I determine the thickness I need? A how do I choose the thickness? All the filters on edmunds seem to have a set thickness.

 

If at all possible, please provide links to any specific products.

[rfcurry]

See the sticky - http://www.ultravioletphotography.com/content/index.php/topic/663-sticky-uvvisir-filters/ for info in the available UV bandpass filters. We will be changing our offerings next week just to keep Andrea busy. ("Idle hands..." :)

[JCDowdy]

AHawkins,

 

Firstly, how deep into the UV do you think you need to image, or do you know?

[AHawkins]

JCDowdy,

 

I am not sure what you mean by that.

[Cadmium]

AHawkings, John means how deep/low of UV wavelength. Which for almost everyone is limited by the lens used, so 320nm is the usual limit unless you have thousands of $'s to spend on a lens.

Also, most UV-only filters have their lower limit around 320nm, so for normal UV photography, you are looking at 320nm as the bottom limit, and given the UV transmission of most affordable older lenses that are capable of 320nm to 350nm transmission 'depth', a UV peek of about 360nm at best.

[Andrea B.]

John is asking you what the expected nanometer range is in which you want to photograph.

 

With a UV-dedicated quartz/fluoride lens + broadband UV-pass filter like the BaaderU used in sunlight or under full spectrum artificial UV light, you can expect to photograph between 300-400 nm (approx) with a peak around 360 nm (approx). [The strength of the transmission lies between 320-380 nm.]

 

With a non-UV-dedicated lens + broadband UV-pass filter used in full-spectrum UV light, you could probably capture UV reflections between 370-390 nm. That is a fairly narrow range of UV. If your chosen subject exhibits UV reflections in the 340nm area (for example), you would not capture them in the photograph.

 

*********

 

Let's go at this differently. Suppose you want a complete professional "broadband" UV photography kit. Yes, it is hugely expensive, but such a pro kit will get you all that is possible to get in a UV photograph with off-the-shelf (later modified) gear. Anything less than this will involve some kind of compromise in UV transmission range, lens quality, camera features, exposure times and more. That is not just my "opinion" there - that's just the way it is with UV photography gear. (FWIW, I've tried most everything by now.)

 

Complete Professional Broadband UV Photography Kit for 300-400 nm range.

• Camera: Nikon D610 or Sony A7RII, converted.
  These are high-ISO-capable, high-resolution, fully-featured cameras.
  

• Lens: Coastal Optics 60/2.8 or Rayfact 105/4.5.
  These currently manufactured quartz/fluoride lenses are corrected for chromatic aberration across their range, so have no focus shift.
  They transmit between approximately X - Y nm. (must look up)
  

• UV-Pass Filter: BaaderU or AndreaU UV-Pass Filter.
  These are broadband, IR suppressing UV-pass filter solutions.
  (I cannot mention all possible filter solutions. These are two I use regularly.)
  

• Lighting: Sunlight or Xenon Flash or Xenon Lamp
  (Sorry, I don't have any specific brands here. Will try to get some.)
  

**********

 

Now, let's go to the other extreme. Suppose you wanted a UV photograph with the least expensive gear possible. There will be many, many compromises in the area of transmission range, exposure times, lens aberrations, pixel resolution, image quality, etc. (But please note that I have seen absolutely stellar UV images made with this kind of inexpensive gear. The talent of the photographer plays a big role in that.)

 

Least Expensive UV Photography Kit for 370-390 nm range.

(Not particularly "recommended", but it will give you a UV image for cheaps.)

• Camera: Nikon D70, unconverted, used. ($65)
  The internal UV/IR-blocker in this cam was very weak, so no conversion is needed.
  There are scads of these cameras available in the used market. They are dirt cheap.
  There is no Live View on the older cameras, so you have to focus before
  you add the UV-pass filter. Adjustments may be needed.
  

• Lens: Nikon 18-55/3.5-5.6G AFS DX, used ($65)
  While we don't have a spectral chart for this lens, we would expect transmission in the 370-400 nm range under good UV light and long enough exposure.
  There are scads of the old version of this kit lens available in the used market also for dirt cheap.
  

• UV-Pass Filter Stack: U360 + S8612, thick enough to supress IR. (approx $65 + $85)
  (I will simply not recommend the current, cheap Chinese UV-pass filters off Ebay. They're terrible.)
  

• Lighting: Sunlight.
  

**********

 

So, you (AHawkins), have to decide where you want to land between these two extremes.

Do lens aberrations matter? Does exposure time matter? Is there a UV reflection range which you must capture? What kind of image quality is important in the finished photograph? Do you care about noise, crop-ability, sharpness? How important is frames-per-second?

 

And we haven't even talked about how to convert the camera file into an actual image. The standard software (Photoshop/ACR) is not always the best choice when working with a UV image.

 

********

 

ADDED LATER: Mr. Hawkins -- If I were you, I would put together the least expensive kit suggested here and test it to see if it gives you what you want. If it does, well then, you are done. If not, then you can send it to Ebay and get your $300 back.

[Cadmium]

I would definitely recommend getting a camera that has live view, the D70 doesn't have live view. So get a D90 or whatever has live view.

I would not recommend the 18-55mm lens for UV. Get some older manual lens that has fair UV transmission capability.

 

Just get a live view camera that is converted to full spectrum. Get some older lens good for UV. Get a UV only filter, or stack, or laminated.

The stack I recommended above (stacked or laminated) is about the least expensive, and will work fine.

 

The set up is pretty much simple, but UV takes some getting use to, so try it out first before you buy multiple copies of all this stuff.

[JCDowdy]

JCDowdy,

 

I am not sure what you mean by that.

 

What is the wavelength range you desire to image?

[Alex H]

There are a number of older manual focus UV capable lenses that you can easily find on used market in relatively large quantities for the same exact brand and model. For some unclear to me reasons I have accumulated a number of identical 35/3.5 and 50/2.8 lenses. Depending on what camera you decide to use, you can easily compile a large set of identical lenses with 35mm (M42 or T-mount), 50mm (M42) or 135mm (T-mount) focal length. They all will be able to record in 320-380 nm range sufficiently well - if used properly, you will not be able to see that much difference between them and dedicated quartz-fluorite UV lens. Other focal length are possible too, but I have not been watching eBay for quite a long time and does not know the current market. Using kit lenses for UV will quickly prove disappointing.

[Andrea B.]

Alex, you have lens knowledge and experience, thus, would you please comment on possible chromatic aberrations in lenses which are uncorrected in the UV range? I am curious for myself and for the membership and would like to see a separate topic on this with a paragraph or two about what to expect. I know you are busy, but when you get a moment or two perhaps you could address this topic?

• What would a user expect to see in the image? False-colour fringing? Softness?
  
• How much aberration is seen in one of the typical 35/3.5 we all use for UV?
  
• What about uncorrected quartz lenses such as the Asahi Quartz Takumar or any other "industrial" quartz/fluoride lens?
  
• Do you have any images showing such aberrations?
  
• How could a user set up a test for aberrations in the UV range?
  

[JCDowdy]

Andrea,

I to would also like to see a separate topic on this. As owner of of a few of these type lenses I would also be willing to participate in any protocol exploring this.

I would like to suggest that proposed topic also include image processing techniques to correct or reduce CA of uncorrected quartz lenses be considered.

After all the Tochigi Rayfact UV-105mmF4.5 (aka UV-Nikkor) and Rayfact IL40mm/50mm/63mm/75mm (AKA EL-Nikkor) lenses are technically now classified by Nikon as industrial-use lenses.

Some of the other "industrial" quartz/fluoride lenses are supposed to be corrected for CA, I would like to know how to access the degree of that correction.

[enricosavazzi]

[...]

• What would a user expect to see in the image? False-colour fringing? Softness?
  
• How much aberration is seen in one of the typical 35/3.5 we all use for UV?
  
• What about uncorrected quartz lenses such as the Asahi Quartz Takumar or any other "industrial" quartz/fluoride lens?
  
• Do you have any images showing such aberrations?
  
• How could a user set up a test for aberrations in the UV range?
  

I have some evidence to offer, albeit more anecdotal/qualitative than quantitative.

 

I tested several legacy lenses in UV, some of them on m4/3 converted cameras (some of the tests are described on my web site), others on a modified Gopro action camera (some of them described in an older post on UVP). Most of the tested lenses are wideangles because this is the focal length range where I (and indeed we on this site) are mostly lacking small-sensor alternatives for UV imaging. None are UV lenses, and all the tested lenses are only usable in the wavelength band starting at 380 or even 390 nm and up. Part of the lenses cover the m4/3 format (a few of them just barely, or not in the corners), others (mainly in C, CS, D mounts) cover only the much smaller Gopro sensor.

 

With a couple of these lenses, I noticed an extreme amount of focus shift between VIS and UV. We know that what we call UV focus shift is axial (aka longitudinal) CA. The focus distance in the NUV with these lenses in close-up photography was literally half the focus distance in the VIS at the same focus setting. These lenses also gave visibly fuzzy images in the NUV, although they performed reasonably well in VIS. I believe that the lenses were designed for a reasonably good control of axial CA in VIS, but this correction peters out sharply at the UV side of VIS. Even with a filter that passes only NUV like the Baader U, the wavelength band is wide enough to show axial CA. It is also possible that some of the fuzziness comes from similarly uncorrected transversal CA, but the whole image as I recall it was fuzzy, including the center (which is not affected by transversal CA).

 

The UV transmission band of these lenses is apparently too narrow for CA to create false-color haloes or the false-color equivalent of VIS magenta haloes. In principle, CA could create false-color haloes in quartz lenses with broadband UV pass filters (at least 360-390 nm, which includes both false-yellow and false-violet). A narrow-band UV-pass filter should on the other hand be expected to give a clearer image with less or no false-color CA.

[Alaun]

Just a side comment on the CAs: I tried in some cases to use the tools in the PS RAW converter/filter to reduce these haloes on UV pictures. You need to adjust the color range, but in some cases it worked quite well as I recall.

[OlDoinyo]

If you do not need the color capability and are willing to work with them, you might also consider film cameras--they can be had for a song, many of them will take the same lenses as some of the digital lines, and the filtration can be much simpler and cheaper because most film has no IR sensitivity and a number of emulsions are much more sensitive to UV than all but the most high-end digital sensors. Often a simple 403 filter will give you a reasonably pure b&w UV image on film.