Clarkey

Are you planning to use it for imaging? If so I would recommend either a R&P focuser or a SteelTrack. I appreciate these are more expensive but for imaging I would say they are worth the extra expense. I have two Baader ST's and I think they are excellent.

Could you not use a side-by-side rig. Or am I mis-understanding the problem?

ADM Losmandy-style Dual Mounting Bar | First Light Optics

Welcome to the slippery (and expensive) slope that is AP....

I would say you starting kit is pretty sensible and will give you some great images and get you used to the processing side of the hobby. If you start with the Samyang 135mm you can always get another lens or two from Fleabay pretty cheaply. I think even a small widefield telescope would be possible later. With regards to the camera, if you are only using it for AP then get it modified. This will give you a much better Ha response and allow you to use things like dual band filters when the moon or LP does not allow broadband imaging. You could go straight to an astro camera, but a cooled version would take up most of your budget. You might be lucky and get one second hand, but for widefield you really need a reasonable size sensor (or mosaics) which makes the DSLR a good option. Also, if you buy a second hand DSLR you can always sell it and get most of your investment back.

With regards to filters more generally, my advice would be to avoid LP filters if you can. As a rule most LP these days is LED and the filters are not really designed for this. Personally get all the data you can and treat the LP on processing. If you keep your subs relatively short that will help.

As for the tripod - give it a go. If you struggle with movement you can get a new one. Just keep the legs as short as practical to prevent it wobbling.

I have a range of kit for different imaging and I am reluctant to let any of it go - for the simple reason it all does slightly different stuff. I think the equipment you listed will still be useable in a few years time for the same reason. Even if you move up to a bigger mount / scope, it as always good to have a portable set up. (In fact it is the next thing on my shopping list when SWMBO agrees).

Good luck.

Welcome to the RC club and the delights of collimation! I use the DSI method (or at least something close). I normal align the secondary first using a Reego (or you can use a Cheshire) then use this method to get the primary right. It works for mine but if there is a lot of focuser tilt it may not work for you.

DSI_Collimation_Procedure_Ver_1.0.pdf

The only thing I would say about putting filters very close to the sensor is that there is a risk of reflections on bright stars. If you don't need the filter too close then having it slightly further away can alleviate the problem. Probably not a problem with your set up, but with some scopes it can be a problem.

At least if it is the glass you might be able to replace it. If it was the sensor - no chance.

Just checked the Altair website. It looks like they sell the glass windows as stock - you might be in luck.

6 minutes ago, david_taurus83 said:

Looks like someone has already had a go at it by the look of that retaining ring..

Agreed. Looks like damage to the sensor - although difficult to tell from a photo. I think you would be entitled to ask the seller about it. 

Looks like dirt in the image train. Different places I suspect and quite bad. You need to check the sensor and any glass / filters near the camera. Just be careful cleaning - ideally just blow dirt off with a puffer but you might need a small lens brush.

I had a very quick go at this and got the result below. Just some curves and level is Affinity.

The data was certainly not too noisy but as stated above there are some minor gradients. Also, the background is pretty light to get the red signal - as Wim says, this is probably down to the CLS filter. FWIW I live in Bortle 5/6 and I never use light pollution filters other than NB, but this is for the moon. I would rather get as much signal as possible and deal with the problems in processing. 

If you are using APP you could split the channels and then work on each separately which would probably improve the final result.

Well done Tomato and Bluester, great images. And well done to the other entrants - some really good images all round 

I think you should enter the 'holiday' competition with this. Great image.

23 hours ago, Anthonyexmouth said:

I guess what I really want to know is whats the extra £££ getting me on the Sesto/Pegasus over the zwo

Not a lot. Unless you are looking for something specific as stated above - both will work on most scopes.

It will depend on how long you want to run it and how cold. It is listed as drawing up to 3A at 12V so at 'full power' it will use up the battery fairly quickly - just over 2 hours. However, if you run it at a higher temp it won't use that much power. If you are running the RPI and any dew bands you will probably want more than this. I have an 85 Ah lead acid for my imaging rig for use away from home. However, this is overkill. Typically my single rig uses 1.5 amps whilst tracking and imaging.

4 hours ago, Felias said:

Bought an 8-inch StellaLyra Dobsonian from @FLO, for my school.

Obviously a much better school than mine. If that had been my school, the tube would have been converted to a canon by now and footballs would be flying everywhere!!

Just try it. It will depend on how fussy you are, sensor size and any minor tilt in the image train. Even where a specific distance is quoted I have always found it an approximation.

I think both would be excellent - pay your money take your choice.

I have the SM90 and it is excellent in terms of colour correction and imaging. The only thing I did find was that when I was running it as part of a dual rig the focus drifted more than the ED80 I was also running. This might be down to the carbon tube slowing the cooling process. However, until I use it some more in the autumn I cannot be sure. The other option is the TS version which is essentially the same as the SM90 but with a metal tube.

Teleskop-Express: TS-Optics CF-APO 90 mm f/6 FPL55 Triplet APO Refractor with Certificate

TS also have a few good value ex-demo scopes that are well worth a look.

Teleskop-Express: Special Offers - Telescopes

6 hours ago, VectorQuantity said:

The connection method to the outside of the focuser collar is a nice idea but assumes the focuser collar is concentric with the focuser shaft.

I might be mis-understanding something, but isn't the collar of the focuser also the outer for the bearings? I'm not quite sure how it cannot be concentric. I can understand 'wobble' if the focuser is slightly misaligned to the shaft - I have had to adjust mine once because of this - but the fault was entirely mine.

FWIW I have used 2 Sesto units on half a dozen scopes and they have been faultless. If I was buying another focuser I would get the same again.

3 minutes ago, Xilman said:

I never throw away potentially useful data. Even if they are not useful for the intended purpose they may be useful for something else in the future. Storage is cheap.

I did not throw it away - but my LRGB image had a very good blue channel!

On 08/06/2022 at 08:06, Scribblecrans said:

I accidentally shot about 45 minutes of data in jpeg before realizing that I shot in the wrong mode.

That's nothing. I did a whole night of luminance data using a blue filter.🤪

Cut your losses and use good data.

6 minutes ago, Avocette said:

I own both APP and PI. My choice these days is to use APP to load Lights, Darks, Flats, Dark Flats, perform Tab 3 Star Analysis to check the quality of my images (useful graphing functions) and then Tab 6 Integration to stack the best of them using the default settings. I use the Tools Tab 9 to Crop the result to get rid of dither edge effects, and then Tools Tab 9 Light Pollution Removal which is absolutely brilliant. Often I save a stretched version of this image as a jpeg to share directly with friends and that may satisfy me at least temporarily, especially if I’m keen on capturing more images of the target. I save all the final integration, crop and light pollution removed images as FITS files. When I am ready to carry out more processing, I import one or other of these FITS files into PI to make use of more delicate control with star removal as an option and also noise reduction. I am experimenting with GHS in PI

I tend to do similar. I stack and initially process in APP and then transfer unstretched files to Affinity or Startools depending what I am doing. For OSC it is possible to separate the 3 channels and process separately before re-combining. I have not tried using it yet, but APP is meant to be very good for mosaics.

The jury is still out on PI. I trialled PI but did not get too far with it - it was like trying to write left-handed! I might give it another go at some point - but at the moment I am working on getting my dual rig up and running.

The tilt plate has the advantage of being fixed, so any tilt will remain the same if you rotate the focuser at all. If you remove the tilt with the focuser you must leave it set at the same point. As you have a rotator it is probably not really an issue for you - but just something to remember if you take your set up to bits.

I have a similar set up with the flattener reducer on my RC8 and I have taped round the tilt adjuster as you have suggested.

Looking at you image there are a few issues, but as a first attempt I would be happy.

A few pointers:

1. I assume you do not have a field flattener from the star shapes - that would help. However, I would not get too hung up on that for now

2. Buy or make a focus mask - it is tricky to get right using the DSLR screen.

3. The dust is almost certainly on the sensor itself. It is too 'clean' to be further away.

4. More total integration time. I would not worry too much about increasing the sub lengths if you are not guiding as you are likely to start getting star trails without perfect PA.

5. Bias, flats and dark flats will be your best option with a DSLR.

To photo M13 you will need very good focus, but good luck. You are on the right track.👍

3 hours ago, Peter Reader said:

I have never tried going beyond 3 minute exposures but I suppose this makes sense - how long would you suggest? can I stack different exposure lengths together in DSS

I'm not sure I would go beyond 3 minutes for the individual subs - in light polluted skies there would be little to gain. Just up the total time. At this time of year and the long exposures the noise from the Canon sensor will just get worse. Your sensor certainly looks cleaner than mine, but it still will still struggle with dark nebula during the summer months and minimal astro darkness.

I had a quick look at some of you images and there is definitely something going on. In terms of the reflections they are odd. Looking at the size they look like they should be from the filters - the same problem I had with my F4 newtonian as shown below. However, the reflections are very different in location. Also looking at one or two of the other images suggests the collimation may be out in addition to some tilt. There is also a weird diagonal on the Baader Lum focus test?

Even though I had no problems with the F5 newt, I did find getting the F4 Photon right was a real pain. I ended up buying a concentre and a new laser collimator (after new focuser and CC) just to get it somewhere close. Not sure this really helps you, other than to say the TS F4's are not easy to work with.

On 18/05/2021 at 12:57, Soligor Rob said:

Ok I was asked to give my first impressions on my Evostar 150ED Pro.

First off I don’t have a great deal of knowledge on telescope or in fact viewing the night sky, I just know I like what I see.

Some of the first reports told accounts of the damaged good arriving due to poor packaging, well Sky Watcher have addressed this problem, the huge cardboard box contains an inner resilient sponge type protective container in side of which is a large aluminum case, with handles at each end and also one central handle.

Beware this is a heavy object.

The Evostar 150ED Pro is a big lump of telescope, already owning the Helios 120mm it is a big step up in size and weight, so be prepared for that.

It has an aperture of F8 so a fair amount of light enters the eye piece.

You might be a bit disappointed in that you don’t get a finder or diagnol in the £1800 price tag, the adaptor fitting on the focus tube is cheap budget at best.

Also the clamp rings on the current batch of telescopes will NOT hold the weight scope by that I mean they spin freely on the tube, why this wasn’t picked up before they left the factory by a simple Quality Control inspection beggars belief.

I replaced them with a set of More-Blue rings and now all is secure.

I swapped the cheap adaptor for a Baader Click lock which is excellent, I also purchased a William Optics dielectric, I also purchased my first Baader Morpheus EP a 12.5mm which is amazing, when available I will also buy the 9mm & 17.5mm.

The massive dew shield which can be unscrewed has for some reason an aluminum end cover, it does have a felt inner protective sleeve but it is inset from the edge of the rim so had taken some paint of the dew shield on arrival.

I rolled some electrical insulation tape around the edge to allow future protection.

Setting up the telescope isn’t too difficult, I’m lucky in being able to walk out of the conservatory double doors straight on to our patio which is were we will be viewing from, Tripod and mount first, I have an Altair Saber Mount sat on top of the Sky Watcher EQ6 tripod which is excellent and more than capable to hold the 150ED.

Holding the scope in my arms it easily rolls into the Vixen dovetail clamp, tightening the screws is an easy task, I have ordered a Losmandy Dovetail Bar which will give a larger and more rigid clamping area.

I also purchased the Geoptic padded bag which makes moving the telescope around so much easier, it is well padded and  fit's the scope perfectly but you do have to remove the diagnol.

Using a Bahtinov mask finding focus was easy, the dual speed focuser being positive with no slippage and a has a god positive feel to it.

Typical I didn’t have long before the clouds moved in so I snapped of a few photos of the moon using my standard Canon 60D.

I processed the pictures in Photoshop C6 merging 3 images together, the other photo is as it came, the most noticeable being there is no Chromatic Aberration which I was well impressed with.

So for the first time setting up despite it’s weight it all went straight forward, sits nicely balanced on the Altair Sabre mount and is so easy to move around, I have ordered the extension tube to lift the whole scope clear of the tripod legs and to prevent me having to crawl on my hands & knees when getting close to the Zenith.

 

 

 

 

 

I appreciate this is an old post, but I was wondering what your opinion of this scope is after a year?

Or does anyone else have any thoughts?

I am considering one for galaxy imaging as it is a lot cheaper than a 130 - 140mm triplet and will cool quicker. I have an RC8 but the idea of a no maintenance refractor does appeal.