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06-09-2020, 08:22 AM   #1
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Is this ist D likely to work?

At the moment, there is an ist D listed on Ebay with the following proviso:

Shutter doesn't fire when lens loaded ,
but it fires well without lens,
flash fires,all keys respond

I am looking for a cheap camera from which to try removing the bayer color grid, and the price looks right on this one, but I am hoping to take some black & white pictures after my try, Full manual mode would be OK, and I have some A and M lenses to try.

Any ideas what might be wrong here? Is a lens contact missing or ....

I'm tempted to give this a try - at worst, I should be able to slide some paper between the lens contacts and the body, in which case the camera shouldn't be aware it has a lens attached!?

06-09-2020, 08:44 AM   #2
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No focus lock, no shutter release. What lenses were used for testing?

A link might help.
06-09-2020, 08:49 AM - 1 Like   #3
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Tricky! The "shutter doesn't fire when lens loaded" could simply be just a problem in the camera settings with a manual lens or lens that's not focusing. That is, it's more a sign of operator error than camera error.

If the shutter fires well without a lens because of an electrical fault in the mount, the worst case fix would be to disconnect the electrical contacts on the mount or slide in some paper like you suggest.

That said, old cameras on eBay are always a risk especially if the seller isn't skilled enough to properly configure and test the camera.

But if the camera is cheap, it might be worth the risk.

Good luck!

P.S. Is this project for some monochrome astro work or other subject matter?
06-09-2020, 09:09 AM   #4
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QuoteOriginally posted by photoptimist Quote
That said, old cameras on eBay are always a risk especially if the seller isn't skilled enough to properly configure and test the camera.
There's one listed as-is says card problems. Could just be they tried it with SDHC cards and not SD.

06-09-2020, 09:10 AM - 1 Like   #5
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If it is a true *istD remember it is a compact flash not SD card

Also it has some very useful functions that k series DSLRs don’t have

Support for P-TTL and true TTL flash so you can use the older TTL flashes with KA lenses and also get flash support for non KA lenses

Use of the body flash as the master for high speed sync with off camera flashes.

But no shake reduction

From memory, if you don’t have the use aperture ring function set, the shutter won’t trip, and detection of a lens is done by the pins shorted on the mount

Also note that the shutter will trip with black body teleconverter, T mounts and extension tubes, unlike k series cameras that need the paint stripped of the mounts to work
06-09-2020, 09:21 AM   #6
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QuoteOriginally posted by Not a Number Quote
No focus lock, no shutter release. What lenses were used for testing?

A link might help.
That's as much detail as there was!
QuoteOriginally posted by photoptimist Quote
That said, old cameras on eBay are always a risk especially if the seller isn't skilled enough to properly configure and test the camera.
Yeah, I kinda suspect user error. There are a couple of pictures of the back and top screens, and they are lit up and seem to be displaying properly (although the back screen has a big crack in it!).

QuoteOriginally posted by photoptimist Quote
P.S. Is this project for some monochrome astro work or other subject matter?
I made a spectroscope. When I take a picture of a gas discharge spectrum (neon bulb, CFL bulb) I get nice line spectra, and don't care too much about the color response of my K-1. But, when I shoot a continuous spectrum, such as a light bulb (the original impetus for this project - I wanted to get a feel for how "good" my lights were for product shooting - i.e. something like the CRI rating), you can see large variations across the visible spectrum from the effects of the color filters in the camera!!!!!!!!!! Nobody seems to make a real black and white camera (at least affordably - if I'm willing to spend a few grand (or a lot more) I could get a Sony/Leica/Sigma/..), so I guess I'll make my own.

For a few hundred bucks, you can get a little digital spectrometer. So far, my out of pocket expenses are $1 for a replica diffraction grating.

Stay tuned - at some point I hope to be able to show the behavior across the visible spectrum of various light bulbs (LED versus CFL versus Incandescent).

---------- Post added 06-09-20 at 09:29 AM ----------

QuoteOriginally posted by Lowell Goudge Quote
If it is a true *istD remember it is a compact flash not SD card

Also it has some very useful functions that k series DSLRs don’t have

Support for P-TTL and true TTL flash so you can use the older TTL flashes with KA lenses and also get flash support for non KA lenses

Use of the body flash as the master for high speed sync with off camera flashes.

But no shake reduction

From memory, if you don’t have the use aperture ring function set, the shutter won’t trip, and detection of a lens is done by the pins shorted on the mount

Also note that the shutter will trip with black body teleconverter, T mounts and extension tubes, unlike k series cameras that need the paint stripped of the mounts to work
Aha, a CF card! Thanks for pointing that out. I think I have a couple that I got from my Dad. I got rid of mine when I went from the early Canon XT/XTi to Pentax.

It has some other useful features, too - a simple plug for external power (I can easily kludge up a 6V power supply) and appears to output TIFFs directly if you want. (Probably lose the EXIF though)

I just convinced myself and clicked "Buy it now"!

Thanks to all for your comments.
06-09-2020, 09:35 AM   #7
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Damn! I found it on ebay.com just now but you bought it already.
Maybe you can cancel it:
The mirror stays up, the display is cracked.
I daubt it that you can repair it.
With cardproblems it can be because if used with a wrong card, but I would not trust it.
The worst offer is this one from India!
Pop-up-flash stays open: This happens when the solenoid is removed and one fiddles the green one in without understanding the mechanisn.
One can see that the screws on the bottom have been opened already, so very likely both solenoids missing.

But with yours, if you can't cancel, then get the two solenoids out and sell them separately.

06-09-2020, 10:14 AM   #8
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The seller has a couple bodies with AF lenses on them. All the lens only sales are MF lenses. Odd are the seller used a MF lens to test the body.
06-09-2020, 03:08 PM   #9
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QuoteOriginally posted by AstroDave Quote
I made a spectroscope. When I take a picture of a gas discharge spectrum (neon bulb, CFL bulb) I get nice line spectra, and don't care too much about the color response of my K-1. But, when I shoot a continuous spectrum, such as a light bulb (the original impetus for this project - I wanted to get a feel for how "good" my lights were for product shooting - i.e. something like the CRI rating), you can see large variations across the visible spectrum from the effects of the color filters in the camera!!!!!!!!!! Nobody seems to make a real black and white camera (at least affordably - if I'm willing to spend a few grand (or a lot more) I could get a Sony/Leica/Sigma/..), so I guess I'll make my own.

For a few hundred bucks, you can get a little digital spectrometer. So far, my out of pocket expenses are $1 for a replica diffraction grating.

Stay tuned - at some point I hope to be able to show the behavior across the visible spectrum of various light bulbs (LED versus CFL versus Incandescent).
Great idea! It sounds like a really fun and worthwhile project. (One that I've thought about, too; have the diffraction grating; but have yet to take the next steps to create the right optical setup to direct the diffracted spectrum on to a sensor.)

Rather than use a monochrome sensor, calibration might be able to correct for the complex sensitivity curves of the Bayer color filters as well as the sensitivity and attenuation spectra of the silicon sensor, camera IR filter, and spectrometer optics.

One calibration approach might be to use a clear tungsten bulb on a dimmer circuit with test shots at different dimmer settings would create a population of smooth-spectrum black-body emission traces. It's then a matter of decomposing the data in the very smooth, easy-to-model black-body curve components and the squiggly RGB filter effects.

Anyway, it sounds like a really cool project!
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