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How to improve results? (1 Viewer)

Mark9473

Well-known member
Belgium
I could probably do with a better camera (now an Olympus E-520) but I don't think equipment is my main problem. Using a 107 mm aperture telescope (700 mm FL, f/6.5) I find that depth of field is just minimal and with birds never sitting still it's a sort of hit and miss whether the photo will be OK or not.

Any tips or experiences from other photographers?
 

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The photo you posted looks fine, there's a slight blue cast over the hole image, probably generated by the scopes optics. Is it a basic acromat, ED or Apo? As far as sharpness the photo is fine. I did a slight adjustmemt of levels and colour in Photoshop, see attached.

I tend to refocus every shot and have just got very quick at focusing. I rarely lose a shot due to poor focus and refocusing virtually every shot I'm sure to get plenty of keepers. You could try fitting a cap to the front of the scope and reduce the aperture slightly. My 80mm comes with a cap that has a 50mm hole in it and this greatly increases the depth of field. On your scope that already has a large aperture you could reduce it and still retain good shutter speeds.

Paul.
 

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Thanks Paul; I don't really get that many keepers due to focus being off when the birds move the tiniest bit. I was focussing using Live View and then by the time the shot is taken the scene has basically changed. I'll have to try other shooting techniques.

Good idea about stopping down a bit to increase depth of field. I'll give tha a try some day. Exposure was 1/250th on this one so there may be some margin if I bump it up from base ISO a bit.

The scope is a triplet apo. I did notice some changes in colour between the different shots so probably the automatic white balance was off a bit on this one. But your version definitely doesn't come as close to reality as mine.
 
I tend to have the scope loose on the tripod so I basically pan around all the time and do all my focusing through the viewfinder. I use continuous shutter and do bursts of maybe three photos, refocus and take a few more. Even down to about 1/50 I'll work in the same way.

Paul.
 
Well from your impressive gallery it's clear you have the technique fully under control. I may try shooting in bursts that way if the bird moves back into the focus range that will resolve the issue.

My mount was a DiscMounts DM-6 on a Berlebach Planet tripod. Pretty solid and smooth, but of course way too heavy to carry into the field. I was actually setting up to shoot the Moon and aimed for a few birds as I was waiting for the sun to set.
 
Hi Mark, Welcome to Birdforum. I have seen your Moon shots and they are great, also two frogs in a pond.;) The one you posted here looks great as well, both versions. Great Moon/Jetliner shot on CN!!
 
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Thanks guys. A new question, I saw something mentioned in another thread here. A "focus trap", what is that? Sounds like something that makes the camera fire as soon as it detects the subject is in focus. How do I go about installing this? I presume it's a specific setting on the camera?
 
Thanks Paul. I read in that article that the lens needs to be set in auto-focus mode. That obviously doesn't work with astro-telescopes. How do you get around that?
 
I think you need to glue a dandelion chip into the part that joins your camera to the scope. It's basically a copy of the electrical contacts that would be on any lens, ebay is a good place to find them. This then tells the camera that the scope is an AF lens.

Even if you can't get focus trap to work, the dandelion chip can also be used for manual focusing if your camera displays any type of focus confirmation when in manual mode.

Paul.
 
If trap focus will work on the Olympus with an autofocus lens, it should work with a dandelion chip - the camera doesn't know it's manual focus, so I think it just waits until it gets the focus confirmation signal, and then fires. At least, it works that way with a D90.
 
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