Quick question regarding long lenses...

[f0xy]

we had some lenses from an old SLR, film type camera, they work with my DSLR so ive been playing today....this is an 80-200mm.

to overcome camera shake ive put the shutter speed right up in shutter priority, to around 250-300, but the image goes darker and darker the higher you go.....i increased the ISO and they came out very good, is it ok to just increase the iso like this, i mean does the quality of the image go down considerabley(sp)?

 

[McBunny]

right
with alot of lenses the longer you go the slower the lense gets, (the aparature gets smaller the F number on the lense e.g. F5.6) that means you need a longer shutter opening

if you have a fast shutter and slow aparature not enough light gets in so the image is dark


one way to help is to increse the iso as you have found out this increases the sensitivity of the sensor so it requires less light at the given aperature and shutter speed but its a trade off between noise


the better way is to slow the shutter down but then you cant hand hold it so will need a tripod or monopod to keep it shake free

the other way is buy better glass

 

[unofficialPete]

Give this a read..
http://www.pbase.com/wlhuber/the_basics

Plus if you expose correctly noise is less of an issue. A properly exposed ISO 1600 picture will show less noise than an under exposed ISO 800 shot that's been corrected.

 

[planetx]

The point was you set the camera on shutter priority, to that end the camera should still of exposed correctly...ish.
If the camera can't expose on shutter priority it will read Lo or Hi.
You will still get an exposure but it will be under or over exposed.
If you were getting the Lo reading then yes you will have to either slow the Shutter speed or increase the ISO....In this case you increased the ISO.
The fact you are using an old lense as you say. says to me it is possibly a manual type lense???
Is the aperture ring manual???
Did the camera have the ability to adjust the aperture??
If it is a manual lense ...did you have any recollection of what aperture the lense was on??
it is possible it was stopped right down???
What were the lighting conditions??
Generally older manual type lense will flash up as F_ _ on a digital SLR.
Were you getting autofocus??
Let me know the camera body/lense type/aperture used and I am sure I can help you out.

 

[f0xy]

The point was you set the camera on shutter priority, to that end the camera should still of exposed correctly...ish.
If the camera can't expose on shutter priority it will read Lo or Hi.
You will still get an exposure but it will be under or over exposed.
If you were getting the Lo reading then yes you will have to either slow the Shutter speed or increase the ISO....In this case you increased the ISO.
The fact you are using an old lense as you say. says to me it is possibly a manual type lense???
Is the aperture ring manual???
Did the camera have the ability to adjust the aperture??
If it is a manual lense ...did you have any recollection of what aperture the lense was on??
it is possible it was stopped right down???
What were the lighting conditions??
Generally older manual type lense will flash up as F_ _ on a digital SLR.
Were you getting autofocus??
Let me know the camera body/lense type/aperture used and I am sure I can help you out.

cheers for the above people


camera is eos350d, the 80-200 lens is 'CANON ZOOM LENS EF 80-200mm 1:4.5-5.6 II'

it auto-focuses fine, dosent flash F _ _ either, flashes up apeture fine on the screen

 

[planetx]

Then perhaps the lighting conditions were too dark.
Think you have answered your own questions whilst trying to sort out the problems already.
Just keep it and save it for the sunny bright summer days.
Be a good lense for track days.

 

[f0xy]

Then perhaps the lighting conditions were too dark.
Think you have answered your own questions whilst trying to sort out the problems already.
Just keep it and save it for the sunny bright summer days.
Be a good lense for track days.

aye hoping to use it at oulton park tommorow, il have a play around, cheers

 

[planetx]

if you don't already own one a monopod would come in handy.