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Imaging with the 130pds


Russe

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Without correctors, the 80ED will win on natural flatness - but it would be incredibly slow at f7.5. But why would you want to use filters (apart from Ha) with a DSLR? (unless you are de-bayering it), you can try clip filters - but that ties you to one system.

Why not use your QHY8L instead?

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Hiya

Oh, I should have said... Yes, with a debayered 1100d. Hmm... I'd forgotten about the 80ED slowness. Can't win, sigh. Do you think it might be feasible to attach a filter wheel in front of the ff? My qhy8l is permanently attached to my 150pds which is staying indoors. I'm trying to put together a rig to use outside and which I'd be transporting to a location which is about 10mins walk away.

Louise

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Ahhh, now I see.

Ive just looked into whether there is a way to use a dslr with a filter drawer - and its a no-go. The shortest 2" filter drawer available is 15mm in thickness, which already puts you over the spacing required.

The only option available it seems is this:

http://www.teleskop-express.de/shop/product_info.php/info/p5909_Baader-Protective-T-Ring-for-Canon-EOS---use-with-2--and-50-4mm-filters.html

Drop Luis Campos a PM to see how he has his debayerd camera set up, perhaps he has found a different solution. Putting the FW before the reducer wont work really, there is a strong chance you will run out of in-travel on the focuser.

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Ahhh, now I see.

Ive just looked into whether there is a way to use a dslr with a filter drawer - and its a no-go. The shortest 2" filter drawer available is 15mm in thickness, which already puts you over the spacing required.

The only option available it seems is this:

http://www.teleskop-express.de/shop/product_info.php/info/p5909_Baader-Protective-T-Ring-for-Canon-EOS---use-with-2--and-50-4mm-filters.html

Drop Luis Campos a PM to see how he has his debayerd camera set up, perhaps he has found a different solution. Putting the FW before the reducer wont work really, there is a strong chance you will run out of in-travel on the focuser.

Hiya

Luis seems to just use a single filter (Ha) and blends with colour images from an undebayered camera. He has some very nice images on his Flickr page. I was thinking about having the fw ahead of the Evostar 80ED ff - there must be plenty of travel room since, without the diagonal, you'd have an extension tube attached? However I don't know if there'd be a problem from an optical point of view with filters further from the sensor?

Thanks

Louise

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Hiya

Luis seems to just use a single filter (Ha) and blends with colour images from an undebayered camera. He has some very nice images on his Flickr page. I was thinking about having the fw ahead of the Evostar 80ED ff - there must be plenty of travel room since, without the diagonal, you'd have an extension tube attached? However I don't know if there'd be a problem from an optical point of view with filters further from the sensor?

Thanks

Louise

Thinking about it, I suppose the focuser travel is lost by using a focal reducer... :(  I only need 25-30mm for the filter wheel. Maybe an alternate refractor? An achromat might do. I suppose I could swap speed for space.

Oh well, back to deep thought...

Louise

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Thinking about it, I suppose the focuser travel is lost by using a focal reducer... :( 

Correct!

When the FF/FR is in place (especially in push-fit mode) there wouldnt be enough travel left to insert a FW and its adaptors ahead of the FF/FR (ive already been down this road!). An achromat might not deliver a good enough field either.

Also, the 1100d from what I've read is the most difficult camera to de-bayer. The 1000d seemed to have more success.

I can see your thinking, in that youre trying to press as many cameras into service at the same time - which does deliver the goods a lot quicker. Its just a case of coming up with the best configuration for the bits you have to hand (easier said than done im afraid!). Im still trying to think of a way to press my 1000d back into service with the 80ED, I had thought of using its two green pixels to collect OIII data at ISO1600 - but on reflection it would present problems when combining the data set with that from the 383/130pds  (the image would be full of red diffraction spikes).

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Correct!

When the FF/FR is in place (especially in push-fit mode) there wouldnt be enough travel left to insert a FW and its adaptors ahead of the FF/FR (ive already been down this road!). An achromat might not deliver a good enough field either.

Also, the 1100d from what I've read is the most difficult camera to de-bayer. The 1000d seemed to have more success.

I can see your thinking, in that youre trying to press as many cameras into service at the same time - which does deliver the goods a lot quicker. Its just a case of coming up with the best configuration for the bits you have to hand (easier said than done im afraid!). Im still trying to think of a way to press my 1000d back into service with the 80ED, I had thought of using its two green pixels to collect OIII data at ISO1600 - but on reflection it would present problems when combining the data set with that from the 383/130pds  (the image would be full of red diffraction spikes).

Hiya

Um, it's not really about pressing stuff into service, it's more the need to have a portable combo I can easily take outside (I live in a 2nd floor flat with no lift...) and that's quick and easy to setup - and on a tight budget, of course! The 150pds would just be too difficult for little me to transport. A shortish refractor seems to fit the bill.. It would be a shame to not use the mono 1100d. In any case, with the local lp, narrowband seems the way to go. A filter drawyer might do - how much focus travel actually is there with the Evostar ED80? Maybe an alternate ED80 make/model would allow it? There must be a way!! I know a mono ccd would be the best solution but I just can't afford one :(

Louise

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Had a bit of a brainwave....

The 130 and 150pds have exactly the same size and type of thread on the focuser (M54 female). So its possible to remove your QHY8, MPCC and EP holder as one unit and screw it on to the 130 focuser tube instead. Not sure if youve ever removed your ep holder before, it can be a little stiff at first  - but it does come off (eventually!). Just remember - righty tighty, lefty loosen (thats how I remember it!).

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Hiya

Yeah, I'm aware the two scopes are the same in that respect but I don't want to disturb the 150pds setup. It sits there quite happily, all focused and ready to go - should there be a break in the clouds! Besides, what would be the point of doing it? I already have a modded 1100d I could use and using a colour camera for narrowband is inefficient anyway. I'm looking at other refractors like the Equinox 80. It's a bit pricey but cheap compared to true APOs and easily portable. I can get a flattener with a long back focus which would give me plenty of room for a filter wheel.

Thanks for your input though - much appreciated :)

Louise

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No prob :)

Have a look at the new WO71 5 element, fast and flat with a large imaging circle. Nearly 800 quid, but thats only 100 more than a new Equinox plus flattener.

Hi

It's a little short and only has 35mm focuser travel and seems a bit 'non-standard'? It's a bit pricey... The Equinox is a bit pricey as well really, especially, as you say, with the flattener (+£170). Sigh. I've been pointed in the direction of the Explore Scientific triplet ED 80 Essential which is less than £500 incl shipping and has good reviews. There must be a crossover where there's a point that it doesn't make economical sense to pay more for a scope that's to be used with a dslr... The intention is to image with narrowband as I already have the filters but osc and LRGB are still an additional option. I might find that I have less lp looking to the west, away from the city, in which case non-narrowband would be much better than I get from my living room! It's like a lot of things - don't know until I try! I might simply postpone getting another scope and simply try out with my ST-80. It's pretty rubbish for imaging but will give me an idea what al fresco imaging would be like and the kind of images I could get looking West. More deep thought. Anyway, I still have to get a laptop and some other bits first... It all adds up!

Thanks

Louise

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Consider also the GSO 6" F4 at only 580mm long it's shorter than the 130PDS. Plus you get a wider FOV (600mm fl) and reduced exposure times.

Hiya

I'm not sure how transportable it would be and I know fast newts are critical to collimate. Plus I'd probably run into the backfocus problem with any newt.

A short frac fits the bill better even though the cost is much higher. It's frustrating that I could buy a 130pds for less than the cost of a field flattener but that's the way the scope cookie crumbles!

Thanks

Louise

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Hi

It's a little short and only has 35mm focuser travel and seems a bit 'non-standard'? It's a bit pricey... The Equinox is a bit pricey as well really, especially, as you say, with the flattener (+£170). Sigh. I've been pointed in the direction of the Explore Scientific triplet ED 80 Essential which is less than £500 incl shipping and has good reviews. There must be a crossover where there's a point that it doesn't make economical sense to pay more for a scope that's to be used with a dslr... The intention is to image with narrowband as I already have the filters but osc and LRGB are still an additional option. I might find that I have less lp looking to the west, away from the city, in which case non-narrowband would be much better than I get from my living room! It's like a lot of things - don't know until I try! I might simply postpone getting another scope and simply try out with my ST-80. It's pretty rubbish for imaging but will give me an idea what al fresco imaging would be like and the kind of images I could get looking West. More deep thought. Anyway, I still have to get a laptop and some other bits first... It all adds up!

Thanks

Louise

Hi Louise,

If u think that you'd be doing mostly Ha due to the LP then you may also consider the WO zenitstar 71, with the dedicated FF/FR it works out about £470.00 which is lot cheaper than the Star 71 and equinox 80, it is very small and light but  with the caveat that some samples are not so well corrected from some of the early reports. Mine seems to be fine and it had a very good review in the Sky at Night mag a while back. The ED 80 is fine but it is slow and it does need the 0.85 FF/FR which still makes a F6.4 scope @510mm of FL.

A.G

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Hi Louise,

If u think that you'd be doing mostly Ha due to the LP then you may also consider the WO zenitstar 71, with the dedicated FF/FR it works out about £470.00 which is lot cheaper than the Star 71 and equinox 80, it is very small and light but  with the caveat that some samples are not so well corrected from some of the early reports. Mine seems to be fine and it had a very good review in the Sky at Night mag a while back. The ED 80 is fine but it is slow and it does need the 0.85 FF/FR which still makes a F6.4 scope @510mm of FL.

A.G

Hiya

Oh dear, I'm 'cross-threading' myself here... Started a separate one asking about the TS APO 90mm...  As mentioned at various places, I need something I can attach a filter wheel and dslr to... This is a headache with most flatteners/reducers.

The TA APO 90 / Revelation has the advantage of being useable for imaging without a reducer though still needs a flattener of course. The Zenithstar 71 is also fast enough for doing that but is a little short. Still, I'll put it on the list! Do you still have the Ascension 80? I saw a couple of images you did with it - looked fine to me!

Thanks

Louise

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Hiya

Oh dear, I'm 'cross-threading' myself here... Started a separate one asking about the TS APO 90mm...  As mentioned at various places, I need something I can attach a filter wheel and dslr to... This is a headache with most flatteners/reducers.

The TA APO 90 / Revelation has the advantage of being useable for imaging without a reducer though still needs a flattener of course. The Zenithstar 71 is also fast enough for doing that but is a little short. Still, I'll put it on the list! Do you still have the Ascension 80? I saw a couple of images you did with it - looked fine to me!

Thanks

Louise

Hi Louise,

Yes I still have the Ascension. It is really a great scope and with a 314L does not really need a flattner. I use a Televue TRF 2008 with it for anything larger. I live just down the road from OpticStar show room so I kind of hand picked it. It also came with a proper test certificate. It is no TAK FSQ but I am very happy with it for the price. The Explore Scientific ones are mainly the same scope but barebone wether they bother testing these before shipping is another matter.

Regards,

A.G

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Hi Louise,

Yes I still have the Ascension. It is really a great scope and with a 314L does not really need a flattner. I use a Televue TRF 2008 with it for anything larger. I live just down the road from OpticStar show room so I kind of hand picked it. It also came with a proper test certificate. It is no TAK FSQ but I am very happy with it for the price. The Explore Scientific ones are mainly the same scope but barebone wether they bother testing these before shipping is another matter.

Regards,

A.G

Hiya

Ok. Yeah a budget essentials version maybe a tested reject or something... But still, might be worth going for. Nice to live near a showroom. You must have quite a collection of scopes now! The Ascension 80 looks nice on the Opticstar page, if a bit too expensive for me...

Thanks

Louise

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Hiya

Ok. Yeah a budget essentials version maybe a tested reject or something... But still, might be worth going for. Nice to live near a showroom. You must have quite a collection of scopes now! The Ascension 80 looks nice on the Opticstar page, if a bit too expensive for me...

Thanks

Louise

Hi Louise,

The Opticsttar 80 ED doublet is a reasonable price and seems to have the same spec as the Equinox 80 but you do get the tube rings and bits and pieces with it. One of the members has one I think he goes by the name  Leemanley, perhaps you could drop him a line for info. The show room BTW will be closing shortly as they have taken over the distribution of the Meade telescopes so they have a bit of reorganising to do so it will be internet ordering for a while. I really do need to make better use of the ZS71 come to think of it.

A.G

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Hi Louise,

The Opticsttar 80 ED doublet is a reasonable price and seems to have the same spec as the Equinox 80 but you do get the tube rings and bits and pieces with it. One of the members has one I think he goes by the name  Leemanley, perhaps you could drop him a line for info. The show room BTW will be closing shortly as they have taken over the distribution of the Meade telescopes so they have a bit of reorganising to do so it will be internet ordering for a while. I really do need to make better use of the ZS71 come to think of it.

A.G

Hiya

It might be a reasonable price but I can't afford it!

Louise

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I've had a 130P-DS since the beginning of August this year and I did this moon mosaic a couple of days after picking it up.

Shot at 2am during a gap in the clouds on 12/08/2014 :p

Scope: 130P-DS

Mount: HEQ5

Camera: QHY5l-iiC

Approx 11 panes in this image of varying qualities.

post-11689-0-92586100-1414005893_thumb.j

A higher quality version with this scope is on my list of 'things to do'

Rob

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Looking clear here all night so hoping to get first light with my freshly modded 450D :smiley:

Think I'm going to go After M42 (Orion Nebula) as I've never imaged it before, any hints or tips on this target?

Also interested to hear from any 130P-DS imagers that use CCDs as I have been given the go ahead by the bank manager to start looking into getting a CCD.

I know Uranium235 has extensively modded his focuser for the 383L, has anyone else come across similar issues?

I'm contemplating a 314L just to get me started but the fov of the more expensive versions are tempting...

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