Some digiscoping experiments with a dslr (2 Viewers)

[Paul Corfield]

Had my Samsung GX-1L for a couple of months now and this is where I'm at after trying many avenues. The scope I have is a William Optics ZenithStar 80mm. Take a look at the photos with accompanying text. Took the photo of the Robin from 35 feet. The camera/scope set-up converts to around 2880mm in 35mm format and I could barely fit the Robin in at that range. Only just made these modifications today so not had time to try any long range birds apart from static objects but it seems good so far. I reckon it will be good for 100/150m at least, maybe more depending on subject.

I tried the teleconverter and the barlow lens on their own but on my set-up they don't seem to produce as sharp an image as when they are combined. That's probably just down to my inexpensive teleconverter and barlow. The teleconverter is a 4 element design so I'm going to try a better quality 7 element design and see what difference it makes. They are cheap enough on ebay. A better ed glass barlow would probably help too.

In the past weeks I also tried using a lens on the camera and shooting through my various eyepieces but it was an awkward set-up so I gave up on that.

Pretty pleased with how it's been performing today and shall post some more as things develop.

Paul.

 

[erniehatt]

Well done Paul, I have the the same scope with a focal length of 545mm f6.8, but not a Dslr, but I do use it with a Panasonic FZ50 12X zoom with good results. Ernie

 

[JGobeil]

Good job Paul. The photo of the Robin is dark but this can easily be corrected. But what matters most - it is very sharp. Your setup should do a fine job at a longer range.

 

[Paul Corfield]

Cheers guys. Yeah, it was dull and overcast when I took the photo but it looks fine on my monitor so maybe it's a monitor thing. I shot this at ISO800 on standard jpeg mode where as I normally always use RAW. Could very likely have got even more detail from the RAW file. Should be able to try some long range stuff tomorrow as the weather forecast is looking clear and sunny.

Paul.

 

[Neil]

Lot's of good detail there Paul. Good work.

 

[Paul Corfield]

Cheers Neil.

Had a chance of some longer range stuff today. The two Great Tit photos were at around 40m range for the 1st photo and about 35m for the 2nd one. I haven't cropped anything off these to give an idea of how much the bird fills the frame, just resized them to 800 pixels wide for the forum.

The Robin was from around 7m range. I cropped the sides of this photo but the height is as shot and resized to 800 tall.

Paul.

 

[Neil]

Paul,
You've discovered the limitation of the DSLR for digiscoping. No zoom function. It's nice to be able to zoom from about 700 mm to 1600 mm as the Nikon 8400 will , or even longer with the P5100 and the A640. Neil

 

[Paul Corfield]

Paul,
You've discovered the limitation of the DSLR for digiscoping. No zoom function. It's nice to be able to zoom from about 700 mm to 1600 mm as the Nikon 8400 will , or even longer with the P5100 and the A640. Neil

I don't see it as a limitation at all. Without any teleconverters I get a nice 700mm lens, with one teleconverter I get 1440mm and with 2 converters I get 2880mm. It's only a matter of seconds to swap them over.

The original photos of the ones above are over 3000 pixels wide so it's a simple case of cropping off what's not needed and the bird easily fills the screen. I digiscoped for years with point and shoot cameras and in just a couple of months of using the dslr I've already got ten times as many photos to keep than I ever had before with point and shoot. Plus from the dslr I've deleted 100's of perfectly good ones and just kept the very best. With point and shoot I used to delete nearly everything I took from a day out just to keep something that was only average. There's no way I'd consider going back from a dslr.

Here's a Magpie from I'd guess 120m but could have been more. I took a 35mm photo with my point and shoot to show the range but you couldn't even make out the bird it was so distant. Sun had already gone down so light was getting poor for picking out detail but it gives an idea of the range with a medium sized bird.

Paul.

 

[Neil]

Paul,
It certainly looks like an easy setup to use. Just watch out for dust in the camera. I have to take mine in again for cleaning.
Have at look at this site
http://www.flickr.com/groups/digiscopers/pool/
All the Portuguese guys are using DSLRs on scopes using different setups. They seem to prefer the Canon 350D. They do have the advantage of seemingly better light down there.
Neil.

 

[Paul Corfield]

Yeah dust can be a pain and I already suffer a little with it. At the moment I just use an ultra soft brush but I'm going to get some Pec Pads and Eclipse Lens Fluid from ebay which seems to be what a lot of people use to clean their sensors.

I'll probably upgrade to a Canon/Nikon in a year or two when some of the older models come right down in price. My Samsung was so cheap on ebay that I couldn't turn it down. In the meantime I'll keep fine tuning my optics.

Some nice pics on that website you posted. Certainly some nice light down there as you say.

Here's a crop from a photo of a Blackbird on my neighbours roof today. Distance I'd estimate between 15 to 20m.

Paul.

 

[Paul Corfield]

Been a bit wet here for a few days so no time to play. Tried out quite a few inexpensive barlow lens configurations that I picked up on ebay and they work very well up to around 20-30m. I guess I'd need to try some expensive apo or ed glass barlows to get more range than that. This week I'm experimenting with my 50mm SMC F2 lens through my William Optics DCL-28 eyepiece. The eyepiece is threaded so it just mounts to the lens via a step down ring. No vignetting at all and the sharpest images at long range I've had so far. Works nicely with my 2X Hoya teleconverter too. A small bird at 40m fills the frame with the 2X added.

Here's a couple of pics from 40m with just the 50mm lens. 1st photo is the wole photo reduced to 800 pixels wide taken using the 2X teleconverter. Second photo is cropped and reduced by 50% to 800 pixels wide using no teleconverter.

I won a Takumar SMC 55mm F1.8 lens on ebay this week which will be superior to my 50mm F2 and I'll try that out and post some pics when it arrives. It will give a boost to the magnification and sharpness should improve.

Paul.

 

[Paul Corfield]

A 7 element 2X teleconverter arrived today that I won on ebay last week. Here's a photo at around 40m range. Works well in bright light and when loads of extra range is needed.

This photo is uncropped, just the original resized to 800 wide.

Paul.

 

[Paul Corfield]

A little bit more experimenting today. For this photo I added a 36mm macro extension tube between the camera body and the 50mm f2 lens. When this was all mounted to the eyepiece on the scope it magnified the image quite a bit. I've only got the one extension tube but you can stack more together to give more zoom plus they come in varying widths. I'd like to get hold of a Pentax 50mm F1.4 lens if I can find one cheap enough and I think with the extension tubes that could be an ideal set up.

Photo was approx 40m range. It's been cropped and the crop was reduced by around 50% in height for posting.

Paul.

 

[Neil]

Interesting work Paul. In order to have a reference point you could set up a tin can or similar at a fixed distance to check resolution with the various setups.
Does the expension tube change the focus point of the scope at closeup and infinity?
Neil.

 

[Paul Corfield]

I'll do some tests with a tin can tomorrow and come back with some answers on how the extension tube works with the focus point. 1.15am here now so heading off to bed.

Paul.

 

[Paul Corfield]

Interesting work Paul. In order to have a reference point you could set up a tin can or similar at a fixed distance to check resolution with the various setups.
Does the extension tube change the focus point of the scope at closeup and infinity?
Neil.

I got my old spotting scope out and tried the extension tube to see how it would affect close focus and infinity. Close focus was brought nearer by a few feet on my scope. I didn't have anything far enough away to try infinity but I could still easily focus on trees that were a couple of miles away and I could focus on clouds in the distance with room still to spare on the focus so I would say it's pretty good for getting to infinity. I'll give it a go tonight when the moon comes up.

After that I put the camera back onto my William Optics ZS80 scope and did a series of test photos with various set ups. I don't have a huge back garden so these were all taken at 10m range.

All the photos are straight from the RAW files and are cropped from the originals but are at 100%, no resizing, sharpening or post processing has taken place. The original photos are 3008 pixels wide at 240 pixels per inch in RAW mode and when resized they look great. All were at ISO400 as it's a dull cloudy day today. My dslr only starts to show really noticeable noise at ISO1600 and above.

There's very little in it and any slight variations are probably partly down to my focusing. The Asahi Takumar 55mm lens gives the biggest magnification and seems to perform the best over a longer range in the field. Some photos I took with it this morning showed very good detail at 40m. The teleconverters start to drop off after around 25-30m but for closer range they are great. As an example the Robin photo was taken with just the 2X teleconverter. I did a test with my Celestron 2X barlow as well but I find the depth of focus is poor with the barlows, edge to edge sharpness can suffer too on the cheaper barlows. I find the teleconverters a better substitute.

All I need to do now is try the same test over a much longer range.

Also remember that my Samsung GX-1L is at the low end of the spectrum as far as dslr's go. I picked mine up for £180 on ebay which is only £30 more than I sold my Fuji F31 for.

Something else I want to try is a William Optics minus violet filter. This basically removes nearly all aberrations, improves contrast and sharpness. I've seen some test photos done with one and it makes a big difference.

Paul.

 

[erniehatt]

Congratulations on your experiments, as I said earlier I also have the same scope, and have tried most of these experiments, ( except for Tc´s) using my FZ50, the nearest focus I achieved was 2.8 meters, but to be honest there really wasn´t any point, too close for any size bird. So far I have seen no evidence that would make me run out and buy a DSLR. I also cannot see any point in bird photography over 30m. Ernie

 

[Paul Corfield]

Well as a comparison this is my Olympus C-5050 at 3X optical zoom through the same DCL-28 eyepiece taken in RAW mode. All of the tests I did with the dslr beat it easily plus I can get way closer with the same scope/eyepiece set up using the dslr.

Paul.

 

[Paul Corfield]

Ernie, if you were only going to work within 30m or less then why digiscope? A dslr with a good telephoto and a 1.4 tc would be all you need. I'm not trying to make anyone rush out and buy a dslr. I was at the point where I wanted a new camera and couldn't see a reason to stick with a point and shoot as there weren't any that offered all I wanted from a camera for the price I wanted to pay while a dslr did.

These were taken at 100m approx using the 55mm f1.8 Takumar lens through a DCL-28 (24mm) eyepiece. Cropped and then reduced by 50% for posting.

Paul.

 

[Neil]

This issue is going to be a bone of contention for the purist digiscoping against the "newer age" digiscopers using DSLRs. As discussed many times the original digiscopers were using Nikon CP 990/4500 with 20-60x zooms on 80mm scopes. The long lens guys were still using SLRs and film (I'm talking pre - 2000 ). This gave the digiscopers a big reach advantage of approx. 3000mm v 840mm (600mm x 1.4x teleconverter ).
Nowadays the digiscopers are still around 2000 -3000 mm (the newer digicams have got shorter 3x lenses on average ) and the DSLR guys are out to 1900mm (600mm x 1.6 x 2x teleconverter ). They can do this with AF too.
As Ernie points out you lose detail over 30 metres unless you have exceptional light.
In order to push digiscoping out there we have to use longer reach,quality digicams and higher magnification eyepieces for smaller birds under 30 metres. Like the Canon A600 or G series digicams with a 45x or 60x eyepieces.
I'm working on a system that will get me around 4000mm reliably but will also run out to 6000mm. Remember the old CP4500 could get out to 9000mm with the 60x end of the zoom eyepiece.
I'm thinking though I still might be better off with a 4/3rds DSLR like the Olympus range. I'm thinking about the new E3 which will give 30 x 2 x 50 =3000mm with a 30x eyepiece .
Anyway lets keep experimenting and having fun looking for the next breakthrough.
Neil.