William optics FLT 98 vs FLT 110

[Deano1]

I'm considering a WO refractor. If the FLT 98 APO and FLT 110 APO are almost the same price why not go for the bigger one? Are there many advantages to the 98? I'd like to be able to use it for some photography too. Sorry if it's an obvious one and I'm missing something.

Thanks

Dean

[ronin]

Cost difference appears to be one of glass.

The 98 uses the FPL-53, the 110 uses FPL-51

I suspect that you would not see any difference, however it becomes appaent that the better glass will cause a 25% extra light gather to be cancelled out.

Which to opt for, I leave that to you.

A purist would go for the FPL-53.

Greeting also, and not sure if you know there is an astro show on at Leamington Spa in about 3 weeks, as yopu are in Oxford it may be a trip out and a chance to see lots of scope laid out in front of you.

IAS

[Deano1]

Ah, that makes sense. Thank you very much for your help.

I did see that show is on thanks and I'm going along to check it out. Fairly new to astronomy, so will be nice to see what's about.

[ian_bird]

Make sure you get one without a Crawford focuser. The later models have a rack and pinion one - which may be OK. But I had a FLT 98 with the Crawford. First one had a fault. Second one slipped under load. So I swapped it for a Starlight Instruments Feathertouch -which I can highly recommend. I can also highly recommend the FTL 98 - optically it seems great.

Cheers

Ian

[ronin]

If you go to the show leave your credit cards at home.

[Gasman]

Dean

There is a new WO scope which was previously only available in the States but now coming to Europe. Its a WO gtf 102 triplet with better focuser, fpl-53 optics, and inbuilt flattener and looks pretty special.

Ian King is getting one in to bench test

Steve

[Deano1]

That sounds pretty much like perfect middle ground, bit more aperture, same quality glass. Will have to wait on the price I guess. Thanks for letting me know.

And Ronin, the credit cards will have to be locked away in a safe and throw away the key I think to prevent any purchase.

Cheers for all the advice.

Dean

[ollypenrice]

Setting the new one aside I'd go for the 98. You'll find it better for imaging and I'd certainly expect it to hold its value better. As Ian says, many of the Crayfords from WO have been pretty awful. The 98 has a major reputation.

Olly

[E621Keith]

FLT98's objective is made by Astreya in Russia, FLT110's objective is made by some company in Taiwan.

Russian optics vs Chinese Optics. FPL53 vs FPL51.

[ian_bird]

Crayford. Not Crawford. Think I must have been thinking of Cindy!

Either way - with a decent focuser - I love the FLT 98.

Cheers

Ian

[Deano1]

Haha, would be the best selling focuser if it had something to do with Cindy Crawford. FLT 98 is looking favorable, I'll ask about this new 102 at the show though.

How about this digital focuser display thing, found that useful?

Thanks

Dean

[ian_bird]

Hi Dean

The digital focuser display is a bit of a gimmick in my opinion. Never used it on the 98 as I very quickly moved to the Starlight Instruments focuser.

There is also one on my Megrez 72 - but I never use that either.

Cheers

Ian

[Deano1]

Yeah I thought it might be, but then I done my first bit of imaging the other night and saw a bit of potential in the idea. What's the 72 like for visual out of interest?

[ollypenrice]

Digital focus is a naive gimmick. If only it were that simple!!

Olly

[ian_bird]

Plus one for what Olly said. Bahtinov mask, FWHM or FocusMax (With Starlight Instruments Feathertouch plus Micro Touch electronic focuser) for me.

I know Olly does not approve of electronic focusers (He prefers to feel the backlash with his fingers) but I love them. Got one on my WO FLT 98 and another on my GSO 10" RCT!

The 72 is lovely for visual. Ashamed to admit I mostly use it as a guide scope.

Cheers

Ian

[Deano1]

I don't have a bahtinov mask, need to get one. I've only done imaging a couple of times, but the potential use I saw was if you focus on a bright star with the camera, then want to use an eyepiece for locating an object which means re-focusing. But you'd then have the original focusing value for with the camera on. I dunno, just from trying imagine without knowing much that seemed like when it would come in handy.

I was thinking the 72 would be great for a travel scope (going to Italy in a month) and for the money seems great.

Deano

[ollypenrice]

I don't have a bahtinov mask, need to get one. I've only done imaging a couple of times, but the potential use I saw was if you focus on a bright star with the camera, then want to use an eyepiece for locating an object which means re-focusing. But you'd then have the original focusing value for with the camera on. I dunno, just from trying imagine without knowing much that seemed like when it would come in handy.

I was thinking the 72 would be great for a travel scope (going to Italy in a month) and for the money seems great.

Deano

You don't want to be taking the camera on and off. All sorts of reasons, and you could never trust the focus measurement. The camera might not go in exactly the same distance. Focus is critical and fickle.

Olly

[Deano1]

I see, I marked my focuser with a marker and used that as a reference to focus the camera when I took it off and on. Must have got lucky. So without a spotting scope to see DSO I guess you just take an exposure and then see if your object is in the frame?

[pubquiz]

Back to original FLT98 vs FLT110 question has anyone done a comparison between the 2?

They are both exactly the same price at FLO and come with the new R&P focuser so what are the differences in use both visually and photographically?

I read the difference re 51 and 53 glass Russia vs Taiwan etc but what does each scope give in advantages/disadvantages in pure performance?.

Does the 53 glass on the 98 glass overcome the advantage of the extra 12mm aperture of the 100mm 51 glass?

Portability/weight would be irrelevant as it would be permanently mounted and well within the mounts weight capability.

Tom

[ronin]

Doubt if anyone has compared the 2 against each other. Simply who is going to spend about £2000 on each scope to then compare them against one another. It is sort of expensive to make a choice of which one. Do you get down to a choice of 2 cars then decide to buy both to see which you prefer?

Both will be very good. If William Yang wanted to send me either one of the two, the last thing I that would pass my mind would be refusing it because it wasn't the other. If he wanted to send me both then he would hear exactly the same numbers of complaints - absolutely none. Would I compare them, well no I wouldn't.

Does the 53 glass on the 98 glass overcome the advantage of the extra 12mm aperture of the 100mm 51 glass?

The 110 will collect more light, it would collect more light then the 98 if it were a singlet flint or crown glass lens and not an FPL-51 triplet.

The question is are 3 braeburn apples better then 3 russett apples.

The 110 will just collect more light, the FPL-53 should just have better correction. Not really 2 comparable parameters.

As said earlier the sensible person would pick the 110, the purist would pick the 98.

However never let the choice of FPL-51 or FPL-53 get in the way, look at the many people that have Tal's, and they would defend them more vocally then people that have either of the above. And a Tal will sell within a few days, or hours, and FLT-98 takes much longer to sell.

[pubquiz]

Hi Ronin Thanks for the reply

You ask who is going to spend 2 grand on each just to compare them? ...well probably no one but reviews are not only done by folk who have bought the scopes ...they could be borrowed, or...one person may have one and a friend another, or...they could be reviewed by a shop...many ways of doing a side by side review without actually buying both.No I don't get to a choice of 2 cars and buy both ...I read test reports on them...preferably a side by side review then decide...don't think car reviewers buy all the test cars either

I agree if My Yang sent me either I would be happy...if he sent me both though I would compare them....if somebody sends somebody 2 brand new scopes I bet most would compare them....who could resist it

The reason I asked if a same reviewer/ side by side review had been done on these 2 even though one is 110mm and another 98mm is that they are EXACTLY the same price/manufacturer/focuser etc ...all other things being equal it would seem a no brainer to go for the 110mm ....just wondered if someone had looked through/imaged through (not necessarily owned) both of them.

Tom

[E621Keith]

....

The reason I asked if a same reviewer/ side by side review had been done on these 2 even though one is 110mm and another 98mm is that they are EXACTLY the same price/manufacturer/focuser etc ...

May be the same price and focuser, but FLT110's optics is made by an unnamed company in Taiwan, while FLT98 is made by Asterya in Russia, a Roscosmos subcontractor who also produces optics used in the International Space Station. That alone should explain why the FLT98 is more expensive per mm than the 110.

Although this doesn't answer your question of which is better, it should explain one of the reason behind the price difference (or the lack of it).

[pubquiz]

Thanks for that Keith

Yes that explains the cost....would be good to see the differences through the eyepiece/camera.

As mentioned in an above post it will also be interesting to see how much the GTF 102 will be when/if a UK stockist stocks it especially as a flattener doesn't have to bought.

All these scopes are outside my finances at the mo anyway (especially as I am saving up for a new mount) but you can always dream

Tom

[haitch]

On 11/06/2013 at 17:05, ronin said:

 

The question is are 3 braeburn apples better then 3 russett apples.

Sorry to resurrect an old thread but I felt this needed confirming - 3 Russetts easily beat 3 Braeburns.