Film SLR body as webcam host - pros & cons?

[Omaroo]

Hi all

After thinking about the photo of the Pentax film body with the webcam PCB mounted inside Paul (1Ponders) put up a while ago, I've been thinking of doing the same to my Nikon N50 - which I will probably never use again as a day to day unit as I still have two other film bodies that are far more valuable to me (Nikon F and Nikon EL) and now the D40 DSLR. I paid $50 for it on eBay so it's absolutely perfect for the job. It still mounts all my Nikon lenses - which is why I'm interested.

After getting involved in my peltier-cooled webcam project I think I'd also like to try doing the film-CCD conversion on the N50 as a bit of fun. It looks relatively easy to mount the webcam PCB with the CCD still mounted where it should be right on the film plane from the back. If I remove the film pressure 'sled' then it would leave plenty of room for the board.

Now - what would I end up with? Do the camera's electronics become irrelevant just because I'm exposing to CCD rather than film? I guess so as the webcam isn't designed to be exposed for a brief time, but rather outputs a constant video stream. What if I were to perform a long exposure mod on the webcam - would it work the way intended then as the shot would trigger the mirror to flip and the shutter to open - exposing the CCD of a brief time?

The N50 doesn't have mirror lock-up, but it does have a bulb setting - so normal video streaming mode would work if this were set. I've just tried it and the mirror stays up with the shutter open until I re-press the shutter button.

Any ideas anyone?

Cheers
Chris

[ving]

not destroying one of your wonderful nikons are you chris!!! :eek:

just buy an old pentax for $20 or less on ebay and destroy that.

[bojan]

The only pro that I can see is that you have shutter and mounting system.
Otherwise it is not a good idea... too heavy, un-necessary bulky and, it is a shame to destroy a collectable item :-)

[Omaroo]

LOL! This one only cost me $50 on eBay a while ago David. It's the other two I cherish.

The beauty of the N50 is that it has a glass-filled plastic body which will be easier to carve into with the Dremel. :D The older all-metal cameras would be harder to chop up I imagine.

[Omaroo]

The N50, as a base model, is very common and cheap on eBay - it's certainly no collectible like the F and the EL are. I'm not after practicality - so the weight/bulk is no issue for me either.

I guess that I could consider the project a lens-mounting system for the webcam. I'm thinking that the ability to use a wide range of lenses on a system that I can either piggyback on the 12" LS200 or a dovetail plate on the EQ5 is worth the cost......

Maybe I'm crazy but I've already taken the back apart.... :screwy:

:D

[bojan]

How do you cope with it's electronics ?
I mean, the shutter may prove to be unusable once you remove something that should not be removed...
Also, you will need batteries...
I was planning similar thing (for wide angle), but with Praktica body. It is even cheaper

[Omaroo]

The bulb feature works to keep the mirror up and the shutter open - and once I replace the battery with an externally-wired 6v DC source power shouldn't be a problem.

I don't plan to actually remove anything as such - it's purely a mechanical job to mount the CCD and board on the film plane with very minor modification. There's even four beautifully-placed screws on the backplane that will aid in mounting the board. I'd have to remove the little speaker from the webcam's PCB - but that's a no brainer as it serves no purpose anyway.

The question I have is what reaching focus will be like - as the focal plane is in the same place - the only difference being the size of the sensor in comparison to the size of a 35mm frame. I hope that I can center the CCD to picj up a 640x480 pixel "window" within the 35mm frame.

[joe_smith]

Omaroo is it so you can use the web cam with the lenses? If so this would be a better option use a mogg adapter. Details here

http://moggadapters.com/astro/ProductList.asp?cat=webcamslr

[Omaroo]

Thanks Joe. Yes, I've seen these before and they certainly look very useful.
They even include the tripod mount thread.

I still like the idea of experimenting with setting the webcam up in long exposure mode and using the shutter at various speeds to see what happens. I'd like to think that I could use single frames as it were. Even if the camera was set to normal video streaming mode at say 30 fps, the shutter could be used to "still capture" moving objects.

I guess it's the experimentation factor that I like the idea of....

Cheers
Chris

[joe_smith]

Go for it Criss, you will never know if you don't give it a go mate ;)

[Garyh]

Hi Chris,What would be handy with this idea would be the viewfinder for centreing objects (that are bright enough). When you can work out your field of view you can draw a box on the the mirror with a fine perm marker.
No need for a flip mirror!!
cheers

[Omaroo]

LOL! Gary - you've hit it on the head! How funny - half the reason I wanted to do this was because of the viewfinder and I never once mentioned that aspect. Thank you for the prompt!!

Great idea outlining the FOV somehow - should be easy enough with 4 dots on the prism.

Cheers
Chris

[bojan]

You meant, on the screen ;)

[Omaroo]

LOL! Sorry - yes, the screen.

[Garyh]

Opps, I did mean the screen...does the Nikon take interchangable screens as well?, if so a real fine matt one would be good for dim stuff..

[Omaroo]

Not fot the N50 Gary. It's a base consumer model and does not have interchangeable screens like the Nikon F, which was a professional mode and has a removable pentaprism. That doesn't mean that I can't take the camera apart slightly to get to it though..... All I need are two dots at the extremities - top left and bottom right.

[bojan]

The only problem that remains will be illumination.. remember, it will dark out there :-)
It may be a better idea to make a shield with appropriate opening in the middle and insert that between the mirror and the screen.

[Omaroo]

Yes - could be a problem. I get annoyed with dust on the screen now, so all I can assume is that a couple of large dots will certainly be visible.... but I'll try applying some removable dots tonight and see.

Cheers
Chris