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TV60+adapter+Tring+DSLR-enough to start with? (1 Viewer)

From what I have read from users of the TV60 Derry is that it suffers from up to 60% distortion of the photo depending on the camera sensor size. The reviewer was using a Canon 20D. It's something to do with smaller scopes of this size, not just the Televue.

Paul.
 
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Derry, this is a Red Herring. It has less to do with objective size than the short focal length/fast focal ratio of the TV60 compared to the TV85. Of course the TV60 F6 will have more field curvature than the TV85 F7, but it will not be visible photographically in a birding scenario since you will never be focused at infinity and the edge-of-field curvature is essentially hidden by out-of-focus 3D background depth of field.

Astrophotography is the harshest test for any lens since focus is at infinity and the subject is essentially 2D flat across the field with the background/foreground stars. Getting pinpoint stars across the image requires a flattener. A flattener is NOT NEEDED for terrestrial photography on an APS-sized sensor dSLR camera!

hope this helps,
Rick
 
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Derry, although those ads on cloudynights look really tempting, I'm afraid I can't use them, since my friend is going to USA for only 4 or 5 days, so in order not to take risks (I'll not be able to return any stuff, and my friend will not be able to understands if it's broken or not) I have no guarantees... to be absolutely sure, I'll have (he'll have) to buy at adorama.com, and get the stuff delivered before he comes to the country. He will have to only take it back to Moscow, and then to Kazakhstan. But that TV-76 on cloudynight.com is a real bargain...

So you guys unanimous in that I don't need Field Flattener 1.1x. I don't really care about the distrortion, but rather about the 40mm increase in focal length (resulting in 400mm) it can give.

The main question still remains open: can I start with only TV60+camera adapter+T-ring+DSLR and is the increase in focal length (40mm) which Field Flattener 1.1x can give, worth the additional $80? I still tend towards the simpliest solution - TV60+camera adapter+T-ring+DSLR.
 
So you guys unanimous in that I don't need Field Flattener 1.1x. I don't really care about the distrortion, but rather about the 40mm increase in focal length (resulting in 400mm) it can give.

Probably worth emailing the guy that you mentioned that uses the field flattener and get his opinion. Any sort of distortion is a bit of a pain and it's nice to take photos without having to crop all the distortion off.

Also ask the guy if he uses any sort of extension tube between the scope and camera adapter so that he can reach focus. You don't want to get all the kit home and find you can't focus on anything at all without an extension tube. It's usual with refractors to need this extension to reach focus so I'd check first.

Paul.
 
One word about distortion - it may show up in test charts but a lot of distortion (especially pincushion and barrel) has very little impact in real-world nature photos - there are very few straight lines in nature. I shoot with a fisheye lens underwater and THAT introduces distortions in a way that dwarfs anything a rectilinear lens can produce - and no one ever comments or even notices it.

Edge distortion, to me, is one of those pixel-peeping issues such as edge sharpness or light falloff in the corners. In the old B&W days, photographers used to darken the edges of a frame subtly in order to make the subject stand out. And when was the last time an image relied on the absolute last bit of sharpness in the edges in order to stand out? But I digress.

Coming back to the point - personally, I wouldnt bother with a field flattener.

Vandit
 
would agree on not buying the field flattener,, been looking at other TV60 photos on the net and sure cannot complain about the edges having issues,,

Derry
 
Paul, I'd like to clarify the Kenko 1.4x option for me.

First, could you give me some specific information on the model I may need? On adorama I found several models kenko pro 1.4x so I'm puzzled. Should it work for Canon EOS only?

Second, again, the way I can connect everything - Canon 450D connects to Kenko, what goes next? T-ring? then Televue camera adapter, then TV-60.
The 1.4x ratio just seems to be right for me.

Any relevant info would be valuable for me.
Thank you again
 
If you go for the Canon body then it's the Kenko Teleplus PRO 300 DG AF 1.4x Teleconverter in EOS mount on the Adorama site.

The way it's mounted is directly to the camera and then it's as you said, T-ring, scope adapter and scope.

After that you can add a macro extension tube between the camera and teleconverter and this will further increase the magnification. A standard 60mm long macro extension tube (see link below) between camera and teleconverter will take the teleconverter to approximately just over 2X power.

http://www.adorama.com/MCAETEOS.html?searchinfo=extension tube eos&item_no=2

Paul.
 
Thank you, Paul, for your info.
Yes, this option looks suitable for me. On amazon this Kenko is $175, a bit less.
I'll get about 500mm focal distance with this teleconverter. Does autofocus work only with Canon lenses? I'll have to adjust the focus with telescope focuser, right?
I think I don't need extension tube, I'll do with 500mm - this is enough.
It's a shame I can't see anybody with such a setup!
Thanks you very much!
 
The Kenko will work fine with the scope, there will be nothing to worry about in that department. That's correct, autofocus only works on camera lenses. All focusing on telescopes is done manually. On ebay you can buy the focus confirmation chips and these can be glued to the scope adapter. Then you will get focus confirmation in the camera viewfinder. You basically get a little green light that comes on when you reach focus and it goes out as soon as focus is lost.

Here's a couple of photos I took with the Kenko Pro 1.4X on my 600mm scope today (840mm with teleconverter). You would be able to get something of a similar quality with the TV60.

Paul.
 

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I'm having good results with a 1.4X Canon TC. However, my results with a 2.0x Tamron Pro TC were not as good...

My focus confirmation chip doesn't work when the TC is used but it is fine with the scope alone.
 
Thank you Paul, your photos are great!
Well, I must have gathered all the info I needed concerning TV60 and its photo accessoirs, and the setup. The last relevant question which I have no idea - will I be able to shoot holding the setup in hands? Is it possible considering equipment weight and image shaking? Should I think of a tripod and if so, which one? Again - something portable, and not pricey.
 
Definitely need a tripod. The reason being because you need one hand to focus the scope and your other hand to operate the camera shutter. More often than not you will be doing these two things at once and possibly following the subject as well if it is hopping between branches or flying through the air etc.

Can't really help on which tripod to get as I have used an old basic one for many years which has served me well. I really need to upgrade and will likely go the Manfrotto route with a decent 3 way head. Main thing is it needs to be able to support the weight and most tripods say what they will take as max load. Also the head needs to be able to lock up and not move once locked. Some of the cheap ones sag a bit once you lock them up and you are forever trying to tweak it to keep the subject in view.

Paul.
 
Paul, a stable tripod and head assembly is nice but your setup will still vibrate on it no matter how solid the base under it is. The DSLR + TC or Barlow + T adapter + long spacers + scope is a long assembly with many weak connection points - it vibrates a lot.

I have a very long lensplate attached directly to the scope which allows me to balance the setup perfectly on the Manfrotto head. A dual lensplate on which I would also be able to attach the DSLR would be needed to solve the problem. And even then, I am not sure...
 
If you change to a camera with in-camera image stabilization like Pentax or Sony you probably could get away with handheld shots with the TV60 if you develop good technique. Because of the helical focuser, it looks/works more like a standard 300mm telephoto than a telescope so is not the beast Jules thinks it is.

Don't know much about the Sony's but the Pentax K20D is a nice pro-level camera with weather/dust seals (might be good to have in your country) plus you can color tune the LCD for better white/color balance control in the field and it has a high-pixel count that allows for significant cropping. The entry-level K200D might be even better deal now too.

cheers,
Rick
 
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Rick, If you read my last post attentively, you will see that I was answering Paul's comments about his setup. Also, I know how big a TV60 is... Paul's setup and mine are almost 3 feet long when fully extended - have you tried digiscoping with that big a rig ?

Also, getting a Pentax or Sony would provide image stabilization but those cameras are very noisy at high ISO compared to Canon or Nikon - IMO, a loosing proposition for digiscoping.
 
Thanks for pointing that out Rick. I forgot it had the helical focuser. The scope is quite small so you may get away doing it hand held. I used to hand hold my small spotting scopes for digiscoping without any trouble, never ever used to take a tripod with me. Just use whatever is around to lean on for extra support.

The sensor comparison website doesn't really translate to real world results and shouldn't really be used as a sole way to recommend a camera. See actual photos on DPReview and the K200D is easily the nosiest of the bunch. Similar story with the K20D. If you wanted to shoot in jpeg then these may not be the best choice. In Raw the Canon 450D still beats both of them. Putting image quality aside then other points Rick mentioned about the Pentax cameras would be nice like camera shake reduction and weather seals. If you were thinking of hand holding most of the time then this may be the way to go but only really the K20D rather than a drop in pixels of the K200D. You still want the cropping power that more pixels afford, especially on a low power scope like the TV60.

Paul.
 
Thank you again guys,
Yes, Rick, that's what I was interested in - could I use the setup like conventional DSLR+lens one? And it seems that I can begin without tripod (TV60 is 1400g, DSLR body - 600, plus rings and adapters - 200 = 2200g) and may develop the technique you have mentioned. As for a camera, I still think of Canon 450, although I really think Pentax k20d makes really vivid photos. For me Canon 450 is just the right combination of pixels, price and ease of use
 
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