DLSR Digiscoping, with or without lens

[SteveOak]

I am looking at digiscoping accessories on the Kowas site and B&H Camera. There seems to be two methods of attachment. One the adaptor mates to the body as a lens would and then another adaptor mates to that and goes over the spotting scope eye piece.

There is another method on the Kowa website where there is an adaptor that screws into the end of the DSLR lens.



How does that work? Does the DLSR lens increase the image size? Any downside?

Kowa makes an adaptor for the Nikon F mount so I am good there. I would like to understand the differances before I buy adaptors.

Thanks!

 

[hoz53]

I am looking at digiscoping accessories on the Kowas site and B&H Camera. There seems to be two methods of attachment. One the adaptor mates to the body as a lens would and then another adaptor mates to that and goes over the spotting scope eye piece.

There is another on the Kowa website where there is anadaptor that screws into the end of the DSLR lens.

View attachment 1670169

How does that work? Does the DLSR lens increase the image size? Any downside?

Kowa makes an adaptor for the Nikon F mount so I am good there. I would like to understand the differance before I buy adaptors.

Thanks!

i wish some people would answer this as I have the same questions you do. main thing i am wondering is if i could see marks on the plates at 1K better with my budget Kowa? looks to me like the mounts all do the same thing. i may have to buy one to find this out. i did post another thread on digiscoping if your interested.

 

[6BRA]

Optical zoom from the camera or phone combined with lower power on the spotting scope will yield the better experience. Even a 5x optical on some phones now with 30x spotter yields 150x. This is far clearer than a kowa tsn 883 with 1.6 multiplier. This is 99x. 30x allows more light imo. If there is an adaptor that allows the dslr with lens to be mounted...this is the way to go. IF GOPRO HAD AN OPTICAL ZOOM it would win hands down due to weight. I think this is where you will run into issue with the dslr. The go pro is perfect size for digiscoping. It needs a optical zoom to be perfect plus it creates its own wifi. Attaching the dslr weight concerns me. Balance stability.
Just some comments from what I have seen.

 

[Fred Bohl]

Steve it would be very helpful if you would tell us what you intend to do with the image files.

However, to try to be helpful let’s start with the basic concepts.

Eyepiece Projection - using the spotter with its lens and the camera without a lens the adapter locates the camera image sensor at the eye point/eye relief position of the spotter lens.

Digiscoping - using the lenses of both the spotter and camera the adapters locate the camera image sensor at the back focus of the camera lens. Note that this normally requires the internal focal plane of camera lens to be at the eye point/eye relief position of the spotter lens which limits camera lens selection or ability to achieve focus.

Books have been written about both techniques but the question of which is preferable is dependent on how the images obtained are intended to be used.

I’m going to make some popcorn and wait for the experts to chime in.

 

[SKWERLZ]

i can’t imagine eliminating extra glass with a direct mount wouldn’t produce a better image. From experience even a phone camera on an adapter won’t keep you from seeing impacts and misses at 2 plus miles especially on a Kowa Prominar.

 

[Fred Bohl]

SKWERLZ

Eyepiece Projection by eliminating the camera lens does produce a brighter and potentially more technically “better” image. However, the image size at the sensor will be small. The diameter will be the objective diameter divided by the magnification of the spotter for example 66mm/60x = 1.1mm and with typical sensor pixel pitch of 0.002mm yielding only 550 pixel diameter which is poor resolution.

 

[SteveOak]

Steve it would be very helpful if you would tell us what you intend to do with the image files.

However, to try to be helpful let’s start with the basic concepts.

Eyepiece Projection - using the spotter with its lens and the camera without a lens the adapter locates the camera image sensor at the eye point/eye relief position of the spotter lens.

Digiscoping - using the lenses of both the spotter and camera the adapters locate the camera image sensor at the back focus of the camera lens. Note that this normally requires the internal focal plane of camera lens to be at the eye point/eye relief position of the spotter lens which limits camera lens selection or ability to achieve focus.

Books have been written about both techniques but the question of which is preferable is dependent on how the images obtained are intended to be used.

I’m going to make some popcorn and wait for the experts to chime in.

I will use it for spotting shots for myself at 1 mile.

A few months ago I got an urge to shoot at a gong of ~ 2 MOA at a mile. I kinda hoped the urge would subside, but it has not. LOL

I do not expect to have someone to sport for me.

I have most of the parts to build an ELR rifle except a barrel which I had to order. Still working on the freebore so I can order the reamer, but there is time for that. I do have a 6mm barrel and a 6 BR AI reamer to shoot at 1,000 yards to have some fun and sort things out while I am waiting on Kreiger to make a barrel for me.

I have found a few things. With no lens on the DLSR you have to physically move the camera in and out to achieve the best focus. If you have a lens you use the focus ring of the lens.

I think, in both configurations, the eyepeice of the spotting scope is retained.

The DSLR lens does have a magnifying effect but I am not sure how much or how to calculate it. I did see the calculations but I'm not sure where I saw it. I'll have to find it again.

Yesterday I found some software to use a DSLR as a webcam to get the live video from the DSLR to a tablet or laptop. I think I can use VLC or something like it to record shots so I can review them if the splash is hard to see.

Why not cellphone? The sensor on a cellphone is in the 5mm X 5mm range. The sensor on my DSLR is 35mmX 24MM. 33 times more sensor area. The 'magnification' of a cell phone is done be simply looking at a smaller area of the sensor. Unlike optical magnification there is no additional image present, it is not actually magnification. Then there is the superior quality of the sensor and the Expeed processing which a cell phone does not have. Plus, the quality of the lens (In this case, Nikon.) on a DSLR is orders of magnitude better in sharpness, distortion (or rather lack of distortion), image accuracy and light transmissivity.

Here is a lens + eyepiece configuration.

 

[SKWERLZ]

I will use it for spotting shots for myself at 1 mile.

A few months ago I got an urge to shoot at a gong of ~ 2 MOA at a mile. I kinda hoped the urge would subside, but it has not. LOL

I do not expect to have someone to sport for me.

I have most of the parts to build an ELR rifle except a barrel which I had to order. Still working on the freebore so I can order the reamer, but there is time for that. I do have a 6mm barrel and a 6 BR AI reamer to shoot at 1,000 yards to have some fun and sort things out while I am waiting on Kreiger to make a barrel for me.

I have found a few things. With no lens on the DLSR you have to physically move the camera in and out to achieve the best focus. If you have a lens you use the focus ring of the lens.

I think, in both configurations, the eyepeice of the spotting scope is retained.

The DSLR lens does have a magnifying effect but I am not sure how much or how to calculate it. I did see the calculations but I'm not sure where I saw it. I'll have to find it again.

Yesterday I found some software to use a DSLR as a webcam to get the live video from the DSLR to a tablet or laptop. I think I can use VLC or something like it to record shots so I can review them if the splash is hard to see.

Why not cellphone? The sensor on a cellphone is in the 5mm X 5mm range. The sensor on my DSLR is 35mmX 24MM. 33 times more sensor area. The 'magnification' of a cell phone is done be simply looking at a smaller area of the sensor. Unlike optical magnification there is no additional image present, it is not actually magnification. Then there is the superior quality of the sensor and the Expeed processing which a cell phone does not have. Plus, the quality of the lens (In this case, Nikon.) on a DSLR is orders of magnitude better in sharpness, distortion (or rather lack of distortion), image accuracy and light transmissivity.

Here is a lens + eyepiece configuration.

Well any remotely decent spotting scope with camera or phone camera can get it done so whatever you do it will help.

This is a $500 bushy spotter and ancient iPhone video

https://rumble.com/v6tzkj1-2020-yards-with-338-edge.html

 

[Fred Bohl]

Steve I should tell you that I’ve been a SRBR (100, 200, 300, 600 and 1000 yards) shooter for 66 years and have no experience with ELR shooting. I have also been an astronomy hobbyist for the last 60 years including photography through telescopes. However, I’ve been experimenting with photography through spotting scopes and rifle scopes for only the last 25 years.

The best advice I can offer is that given the equipment you have the camera mounting method in the picture in your #7 post above will be best. Further, start with both the camera and spotter focus set for infinity which is then A-focal (without focus). At long range this may avoid the difficulty of focusing given the long depth field and depth of focus. I’ve had good success with this method at 1000 yards.

Best of luck with your ELR journey.