Digital camera sensor to replace DSLR

[jnowat]

I've been through my first test run with the 3D modeling. I used 50 different angles, with 36 around the equator in 10deg increments and some outlying angles, and got better results than I had anticipated with plant matter.

I am in the process of acquiring Mitutoyo Plan Apos now, but I have been thinking about DSLRs (the T1i has treated me well) versus other imaging solutions.

I have been pondering how to set up a tube lens properly on a stackshot (maybe from ThorLabs) and position a digital sensor on it to take my stacks with. I don't have much of a basis to expand on, however, so I was hoping you all had some input you might share.

Right now, it looks like I may have to take 150,000+ exposures per model, and as I'm sure many here are aware, the T1i has a rated life of around 100,000 exposures wherein the shutter eventually fails.

How many exposures would a digital sensor provide over its lifespan? What are the ups and downs of CMOS vs CCD when it comes to focus stacking as seen here on the forums? I'd like to have 10MP at the least, and I don't plan on going over 20X magnification at any near time.

Pictures are encouraged if they help you explain things or provide examples.
Thank you for your advice!

AdminCS edited to add spaces between paragraphs

[pierre]

It seems Sony A7s and Fuji X1-pro have full electronic shutters so it should be OK.

Guess the remote controle may be a bit difficult but not impossible.

Anyone can confirm ?

[Chris S.]

Jnowat, I hope you’ll pardon me for admin-editing your post to add spaces between the paragraphs. I’m pretty sure you meant to do this, and I found it difficult to read your post without them.

I have been pondering how to set up a tube lens properly on a stackshot (maybe from ThorLabs) . . . .

Were you thinking of an integration similar to what I did with a Mitutoyo MT-1 tube lens, but using a Thorlabs ITL200 tube lens? If so, PM me—I made a tentative parts list for doing this, and would be happy to share it. I put this list together out of interest, but have no need of another tube lens assembly, other than the fun of a doing an integration and comparing it with my Mitutoyo assembly—and this has not been a compelling enough reason to spend the money on parts. However, I’d be quite interested in seeing it get built.

As you likely know, the Thorlabs ITL200 tube lens is often available from an eBay vendor, at substantial discount to the new price. If the fellow runs out, I bought a couple of them and could part with one. I also have a couple of Mitutoyo MT-1 tube lenses that I’m not using, if you care to go that route. But a Thorlabs assembly would be considerably cheaper to build than the Edmund Optics assembly I made for the Mitutoyo tube lens.

. . . and position a digital sensor on it to take my stacks with.

I’d be thrilled if you accomplish this and show the rest of us how to do it. Or if anyone has found more information than I have, let's hope they share.

For a long time, I’ve wished we could buy a digital sensor and mount it in our macro rigs, without all the other stuff a DSLR includes, such as a shutter. And actually, we can integrate a sensor in a box of our own making—if we’re willing to use a small sensor, or a largish one made with old technology. Kodak used to support this, and last I checked (a couple of years ago), the Kodak unit had spun off, but was still supporting this sort of integration. As I recall, you would purchase the sensor and a frame grabber, then use their SDK and drivers to build your own integration. They had supporting documentation for this. The deal breaker to me was that the best sensor they offered was circa year 2000—practically stone age technology, in the rapidly-advancing world of sensors. I recall seeing an astrophotography camera based on this sensor. I’m sure it would work fine for macro, as well—but who wants a ca 2000 sensor?

It’s possible to buy replacement sensors for late model DSLRs. I occasionally look to see if anyone has disclosed how to integrate one into a simple, shutterless camera. So far, nothing. My bet is that it could be done by someone with a lot of knowledge and dedication, but for most of us, it would be far from easy. Perhaps someday, an engineer already familiar with the art will quit Canon, Nikon, Sony or the like, and bring to market a simple sensor-box camera for macro, micro, and astro photographers. If it’s reasonably-priced, well implemented and supported, has an open hardware and software environment—and is upgradable as sensors evolve—this person will own a market segment. It will be a specialized market to be sure, and probably wouldn’t support a big company. But it might support a small company rather well.

It seems Sony A7s and Fuji X1-pro have full electronic shutters so it should be OK.

Guess the remote controle may be a bit difficult but not impossible.

Pierre, I was surprised to read this, and went looking. It appears that since Sony offered a firmware update to the A7s, there is indeed a fully electronic shutter option. However, this camera is full-frame (too big for the high-quality image circle of most microscope objectives, though some folks will disagree with me and offer ways they side-step this issue), and rather low in megapixels.

The Fuji X1-pro seems more likely--APS-C sensor (so a cleaner fit to the image circle of microscope objectives), and high megapixel count. However, I didn't, in my quick search just now, see anything about a fully electronic shutter. Can you (or somebody) kindly provide a reference?

Agreed--even if these cameras provide electronic shutter nirvana, the lack of robust remote tethering is a big issue.

Cheers,

--Chris

[mawyatt]

Chris,

Santa Barber Instrument Group, SBIG, has astrophotography cameras that might be useful. I have an old one that utilized a Kodak image sensor. These cameras have thermal electric coolers to cool the sensor, which improves the noise.

[jnowat]

Yes, thanks, I will be sure to space my paragraphs from here, out.

I thoroughly enjoyed the post you linked to, and yes this is part of what I wish to achieve- building an infinity lens tube at 200mm. One quick question; I was perusing ThorLabs website today and found the ITL200 infinity lens, but their specs seem to show that I will be over my 200mm preference if using it to their defined lengths. Would you care to confirm this assumption or elaborate on it?

My next concern is a proper sensor. I realize which APS-C I'm working with currently in the T1i, but is CMOS better overall than what I could get with a CCD? I have to say I'm overall pleased with what I have, but if I could come across something even better, I'd prefer to consider it. I'm thinking somewhere along the lines of a CMOS camera for microscopy, above 10MP, which I can tether to the computer to meet my needs.

Questions which arise from this and on my mind currently:

• How do I manage control through the StackShot, of the exposures? I'm sure it can be done, just not quite sure in how many ways.
  Will the camera stay positioned for this tedious, accurate imaging?
  Will I get equal or better results that with my T1i, concerning resolution?
  Will I find problems with proper lighting- ones which significantly differ from common discrepancies with a DSLR?
  Is an iris necessary for this tube lens (you used a DSLR, but I will have none, so what will an iris do for me)?

I am also interested in astrophotography and have a 10" dobsonian which I enjoy taking out from time-to-time, so if I could get hold of a camera which I could use in either setup, good things would come out of it and I would have dual-uses for my equipment.

I would like to know more about the tube lens you linked to. I think it's fantastic, though I will try to go about purchasing such items used for the sake of my student's wallet.

[pierre]

Chris,

You have the point for the A7s.

Regarding the Fuji X-T1 and the X-Pro1, since a few days they have released the Firmware 3. It allows full electronic shutter, but is with limitation since the flash will not work.

They also provide a new tethering system.
Link: http://www.fujifilm.com/products/digita ... es/others/

Well, all this need to be tested... but it seems pretty interesting

[Chris S.]

Thanks, Pierre! Very helpful information.

But it's disappointing. Personally, I could live without flash during electronic shutter operation, since my studio macro work is increasingly done with continuous light. But the range of shutter speeds available with electronic shutter, 1/32,000 second through 1 second, would be too limiting for me.

It appears that Fujifilm was not thinking of us when they implemented this feature: "However, fast apertures are difficult to use if the light is too bright, so to ensure users can create shallow depth-of-field effects, the camera is now equipped with a fully electronic shutter offering a maximum shutter speed of 1/32000sec. The mechanical shutter will not operate at all when any speed for the electronic shutter is selected, which also delivers a completely silent shooting experience; perfect for shots of sleeping children, pets, weddings, and more. In addition, it is possible to set the electronic shutter in 1/3 steps from a range of 1sec to 1/32000sec." (Source.)

So Fujifilm's intent was to facilitate shallow-depth-of-field portraits in bright light. Not a bad thing, but not what we're doing.

Cheers,

--Chris

[pierre]

Hi Chris,

Effectively, Max duration limited with 1 second might be troublesome.