TS Optics Doublet 80 ED APO and FPL53 Doublet 80 SD-APO

[Vulisha]

Hi all, 

I am having trouble finding images and reviews for this two doublet scopes 

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p7169_TS-Optics-ED-APO-80-mm-f-7-Refraktor-mit-2-5--R-P-Okularauszug.html

And

https://www.teleskop-express.de/shop/product_info.php/info/p8637_TS-Optics-Doublet-SD-APO-80mm-f-7---FPL-53---Lanthan-Objective.html

Third option would be SW evostar 72, and there is more than enough data for that. 

 

Does anyone have them, and even better, some images captured with 80? I am even able to find images for 102 but not for 80. As @vlaiv pointed out to me in PMs cheaper one is basically same model as Altair Starwave ASCENT F7. But again hard to find data for 80

Edited May 7, 2021 by Vulisha

[david_taurus83]

Hi. I have the Altair Starwave 80 EDR which is basically the same as the the TS FPL53 scope. It's a nice well built scope. I had the 102 version prior to that and got on well with it with a DSLR so I decided to get the 80mm EDR. I have only used it with a mono camera so far though and only completed 1 picture. The 102EDR was absolutely fine with a colour camera (Canon 6D) so I have no doubts the 80mm will be just as good. Here's my one completed narrowband image with the 80EDR.

 

[Vulisha]

This looks brilliant indeed! there is small amount of blue on right halfes of brightest stars but it is barely noticable, and much better than refular 80ed. Do you mind me asking what FF you used for this, as stars are spot on all around? 

Edited May 7, 2021 by Vulisha

[david_taurus83]

1 hour ago, Vulisha said:

This looks brilliant indeed! there is small amount of blue on right halfes of brightest stars but it is barely noticable, and much better than refular 80ed. Do you mind me asking what FF you used for this, as stars are spot on all around? 

Thanks! This was taken with an Atik 460 and the Altair 0.8 reducer v2. I have a little bit of tilt in this image so stars are not quite perfectly round but close enough.

[vlaiv]

Regular AA 102mm ED - with FPL51 glass does have some color fringing due to CA

and to be honest, I've seen couple of cases with AA 102mm ED-R which has FPL-53 glass - with also a bit of blue around bright white stars.

I do know 80mm F/7 is going to have less. Do you have any images with OSC sensor and that particular scope?

[david_taurus83]

6 minutes ago, vlaiv said:

Regular AA 102mm ED - with FPL51 glass does have some color fringing due to CA

and to be honest, I've seen couple of cases with AA 102mm ED-R which has FPL-53 glass - with also a bit of blue around bright white stars.

I do know 80mm F/7 is going to have less. Do you have any images with OSC sensor and that particular scope?

No, I've only ever put the Atik on it. I've never even looked through it!

[Vulisha]

Since it seems there is not a lot of experience with 80mm TS Optics I think I will go safe route and go for Evostar 72 with OVL flattener but will think about it a bit more.  

Edited May 10, 2021 by Vulisha

[vlaiv]

Maybe this thread will get more attention in Scopes / whole setups rather than Getting started with imaging.

By the way - I've got 80mm F/6 triplet from TS and I'm really happy with that scope - but I'm not sure if we can extrapolate performance between these two scope lines (triplet F/6 and doublet F/7)

[Vulisha]

I asked mod to transfer thread, thanks on the tip. 

Well I have no doubt that triplet is much better, as it is pricewise  . I indeed did found a lot of triplet images, and they are brilliant, but I did not find any 80mm F7 fpl53 doublet images.  

[DesertSky]

Astro Tech, Altair and Teleskop Express offer almost identical products. They offer doublets for lower price and triplets for a higher range. Triplets may have a slightly better color correction. They are all good for observing and imaging. I would watch for the First Light Optics's offerings because they have even better products.

[Vulisha]

What would be equivalent 80mm in FLO? Mind you that I would need to pay import taxes from UK as well as I am based in EU.  Thanks on the tip about Astro Tech and Altair as equivalents. 

Edited May 14, 2021 by Vulisha

[DesertSky]

If you search keywords like doublet and apochtomatic, FLO will list many TS-optics, Vixen' Tele Vue, Skywatcher and Takahashi products. Pricy ones usually have FPL53 or FC-100 glass but the economical ones have FPL51 or FK61 glass that may be technically slightly inferior but they still satisfy hobbyists.

[david_taurus83]

@Vulisha What are you worried about specifically? You mentioned my image above has some blue fringing but it's an HOO image processed with stars removed and I used Ha as Luminance to add stars back in so it's single channel stars!

[vlaiv]

1 hour ago, david_taurus83 said:

@Vulisha What are you worried about specifically? You mentioned my image above has some blue fringing but it's an HOO image processed with stars removed and I used Ha as Luminance to add stars back in so it's single channel stars!

I don't think he said that.

I mentioned that I've seen images taken with the same scope as yours that shows blue fringing when used with OSC sensor.

For example - look at this thread:

There is stacked data posted that you can examine.

I did quick process on it and blue bloat popped out around brighter white(ish) stars.

[david_taurus83]

I don't have the 102EDR anymore but never had any blue bloat issues with my modded 6D (LPF1 still in place) and IDAS filter. Because it was so good I bought the 80EDR on the strength of that. But I've not used it with the 6D yet so can't compare. Given the price there's got to be some compromise expected. If you really don't want any chance of CA then it's a triplet I'm afraid and the cost that comes with it. I wouldn't buy any refractor for imaging unless it has FPL53 at minimum. And the SW 72ED doesn't have FPL53 anymore either.

[vlaiv]

I think you are quite right - between the two mentioned scopes at the beginning of the thread - better option is one with FPL-53 glass and given that price difference is small - it stands to reason to go for that one.

One can also expect a bit of star bloat in blue - little bit less than in example given in a thread above which shows 102mm model - smaller aperture shows less CA everything else being equal, so 80mm F/7 scope will have less of it. It won't be perfect, of course - but there are options available like Astronomik L3 filter for example to be used with OSC cameras.

[Vulisha]

Well in the end I think I decided to go woth worse but "safe" choice: Evostsr 72.

While there will be for sure blue bloating, the main choice reason is that evostar is available now and TS optics wont be for minimum of 30 days, and in case of need evostar will have higher resell value, and I will be able to replace it easier.

I also read that you can have blue bloating on fpl53 triplet and not have it on 51 doublet. Many factors come in play there not only type of glass. 

 

In the end 80mm fpl53 will stay distant wish and will maybe come one day, but limited data and availability made me stay away for now. Money is here now and it is itching me to be spent