SLR Camera

[liamsantini]

I have recently brought a Praktica BCA electronic 35mm camera, its a great piece of kit for the age, but not had a chance to use too look at the night sky.

Any ideas how good this little bit of kit will be?

[barkis]

Find a reasonably dark site way from artificial lights .

Stick it on a Tripod with a 50mm lens, point it at a spot in the night sky. Set the ISO to 400, and Bulb exposure to 25-30 seconds, and see how it does.

If it's totally electronic, and the shutter depends on tha battery, then limitations might become apparent in very cold conditions.

Experimentation can teach you a great deal, but if you feel the camera can work for you, then lots of help and guidance will be given by SGL members..

If you intend using it on a telescope, the certain adaptors will be needed. You said SLR, so I'm assuming it's a film camera.

Ron.

[liamsantini]

Yes it's film, never used one before, so its all new to me.

The lens on it goes from 70mm - 210

[Glen]

I dont know much about that type but this goes for all film astro work. The first picture on the film should be one of daylight or a bright object, that way when you have the film developed the guys can tell where one shot ends and another begins.

it'll save them cutting your pictures up, also my be a good idea to metion they are astro shots so as to avoid the stickers of 'check exposure settings'

Regards

Glen

[barkis]

Lots of good Images were captured with SLR cameras well before Digitals came on the scene.

70mm will suffice for grabbing some star shots, but try at 15- 30 second durations to see how the trailing comes out, if any.

The 210mm can be used to get some lunar shots. although the image on film won't be very big, and it will need resized.

I've no Idea what film choices there are these days, but a look in your local Photographic shop will provide the answer.

Ideally, your camera should be piggy backed on a driven telescope, or a home made Barn Door mount, which will enable longer exposures to be made. I realise you are just throwing the Idea around, and you may not wish to spend money on this, and thats fair enough, but it will limit your options somewhat.

I concur with Glen, the first or last image you take should be in daylight to mark the beginning or the end of the run. It helps in aligning the film.

I always asked the developer, that the film remained uncut, and returned as a roll.

Ron.

[liamsantini]

Ok I sort of understand some bits there lol.

What do you mean by exposure times?

[x6gas]

I used to have one of these back in the day. They actually weren't too bad. Made in East Germany IIRC (dates it somewhat!)

The exposure time is the length of time that the shutter is open for. You'll need to get a lockable cable release which for that model screws into the top of the shutter release button (notice it's threaded?)

I seem to recall that it is best to set the camera to manual and remove the battery as long exposures will drain the battery in double quick time. Then set the shutter speed to 'B' (stands for bulb and basically holds the shutter open for as long as you have the button pressed or the cable release locked open).

The lens is a 70-210 sliding job, yes? In which case there is a fair amount of glass in there which brings in its own problems. Back the aperture off by one stop (the aperture is the size of the hole in the lens that lets the light - lower the number the bigger the hole so set it to one back from the lowest number by rotating the ring on the lens).

I think with an ISO 400 film you'll need rather longer than 30 seconds to get anything meaningful (that lens doesn't help) but it's best to try a variety of exposure times up to a few minutes though you'll have noticeable star trails by then. Make sure that in your first reel of film you point it at the pole star and leave the shutter open for 15 minutes with a smaller aperture - you should get some nice circular arc star trails around Polaris. Higher than ISO 400 and things start to get grainy but I did have some good shots with good quality 800 film.

As has been said, do tell whoever is processing the film what's on it. If you have a local high street film processer where the process on-site with a mini-lab (rare these days) then have a chat to whoever is going to run the film through the machine. I suspect they'll enjoy the challenge.

I've got a picture of Jupiter somewhere taken with one of these at prime focus on (I think) a 0.8m optical telescope at Observatorio Del Teide, Izaña (on Tenerife) which is still the best astro shot I've got (though that was the professional scope rather than the camera!) Had it processed in Boots!

Have fun, though to be honest by the time you've shelled out for film and processing you might find the convenience of a digital SLR will be too tempting for the extra money, especially for the instant results.

My Nikon D40 seems to do okay (took first DSO pix last night) and has the advantage of weighting less than some eyepieces!

[liamsantini]

Yes, that's the camera, I got it from a car boot, it all works, fantastic little thing.

What you have said sounds great, an I can't thankyou enough for the advice, as you have had one of these, and told me how to use it, I feel at ease now.

The film I have is 200, but will be getting 400 soon.

Oh yes it does have the sliding job, is this good or bad?

[x6gas]

Oh yes it does have the sliding job, is this good or bad?

The lens is fine, it's just that if I recall those sliding macro lenses have a lot of optical elements which I'm told slows the lens down and may introduce some chromatic aberration noticable in astrophotography.

Anyway, like I said I had some quite nice shots with this kit and there is plenty you can do with it - especially if you get or make a barn-door mount. All part of the fun!

Cheers,

[liamsantini]

Hi, just a quick question again, the shutter is open all the time isn't? When I look through I can see stuff so take a picture.

Taken battery out, and put it on to bulb mode, locked and loaded and took one picture.

I'm confused lol

[x6gas]

Nope. When you look through the viewfinder you are seeing the image from the lens projected up to the eyepiece by a mirror. When you take a photo the mirror swings out of the way and the film is where the image is formed. As the shutter closes the mirror swings back down. That's why the image in the viewfinder disappears while you are taking the picture.

In bulb mode the shutter should stay open for as long as you have your finger on the button (or it held open with a cable release). If the shutter opens and closes even with your finger held down on the button then you have a version of the camera that uses a default exposure time (shutter speed) when the battery is flat or not present. That's bad news for astrophotography and your choices are:

1) Reinstall the battery - this just means that you'll get through lots of batteries (which gets expensive)

2) Use an external battery or other power source hooked up to the battery terminals (just needs to be right DC voltage and current)

3) Mod the camera to override the electronics. This would kipper the camera for normal everyday use and I have absolutely no idea how to do it!

Hope that this helps!

EDIT: By current in 2 above I mean, of course, that whatever the power source it needs to have enough juice to keep the shutter open for however long you need. The camera will draw the current it needs... sloppy terminology for which I apologise!

[liamsantini]

Right ok, thankyou so much for your help. I'm considering just buying a digital camera, and selling this one.

I really don't know how to use it, and would be better of with a collector or someone who knows how to get the best out of it.

Film is expensive and so are the batterys

Batterys - £2.50

Film - £4-£6

The money I would spend I could by a digital camera, with a re-charge battery and a small sd card.

[x6gas]

I'd keep an eye out for a cheap second-hand digital SLR if I were you. Remember that for astrophotography (if that's all that you want it for) then picking up a camera with a broken autofocus / light meter / flash etc is no problem (don't use any of those for astrophotography).

I've been pleased with my Nikon D40 and it is very light if you ever want to mount it on a telescope...

My local Sainsbury's is selling 8GB SanDisc SD cards for under 20 quid (that'll store 1000 images in RAW format or 2200 fine JPEGs

[Cunhaval]

If you can do it, go for a digital SLR - it's MUCH easier! Film was good in its day, but things have moved on

Only know about Canon gear, but if you can track down a 2nd hand one, look for 300d, 350d, etc, up to 1000d. Though they are the lower end of Canon's market, they will do everything you are likely to want to do in astro, and they are light enough to mount on a scope.

"Two-digit" Canons (20d, 30d, etc) are even better specced (most of which you won't need for astro) more expensive, but are noticeably heavier.

"Single-digit" Canons (1d, 5d, 7d) are superb cameras, but very heavy, and very expensive indeed!

Good luck

[StarryEyes]

Right ok, thankyou so much for your help. I'm considering just buying a digital camera, and selling this one.

I really don't know how to use it, and would be better of with a collector or someone who knows how to get the best out of it.

Film is expensive and so are the batterys

Batterys - £2.50

Film - £4-£6

The money I would spend I could by a digital camera, with a re-charge battery and a small sd card.

If you are wanting to use film or keep the camera and use it just for general photography you could try this. Works out cheaper the more you buy.

7dayshop.com - Online Store

This is 36 frame (amount of pictures you can get on the film) film there is a 24 frame film as well which works out a little bit cheaper again but you wont get as many photos on it.

[StarryEyes]

Actually, just to follow that up the 36 is defiantly better value for money as multiple purchases of the 24 is actually more expensive. Logically it shouldn't work like that but it seems to have.