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Midnight_lightning

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Everything posted by Midnight_lightning

  1. They should be easy to rotate and lift, I was wondering more about whether they might flex laterally in a breeze, that sort of thing.
  2. Thanks, that is really useful. Do you think the threaded stand-off legs on the dolly will be rigid enough for imaging? If I go down the dolly route I was thinking maybe not use these and just lift each side an put a brick underneath?
  3. I currently have an HEQ5 and Esprit 80 left set up and carry it out for each session. As you say the 120 and EQ6 would be to heavy to lift so I am thinking leave it set up and wheel it out - I only go 10 feet over a hard surface. Since posting I'm now thinking have 3x 3 wheeled "coasters" - put one under each tripod leg - wheel it out and lift each leg individually to remove coaster once in position.
  4. The mounts fine, its me wanting perfect balance. Since I had the stellar tune done the mount rotates very freely - with the clutch off you could gently spin the RA and it will just keep spinning for quite a while. When balancing it with the EFW anywhere other than vertically up of down (home position) I can only get balance on one side of the pier or the other. So balance it one side and I can let go in any position and it just stays. Move to the other side and its not balanced. Took me a while to work it out but its because the CoG isn't symmetrical without the EFW vertical - it only affects Dec balance. I'm sure the mount could handle the mis-balance, before the tuning I wouldn't have even being able to detect it due to stiction, but I put so much time, effort and money into this hobby I am looking to get the best out of everything
  5. That's interesting If I rotate from the focuser for framing the weight of the filter wheel being offset from vertical throws the mount out of balance. I suspect I'm also going to have an issue with the FW or Lodestar (they stick out on opposite sides) colliding with the mount when used with the 120. I may be able to reduce the risk by adjusting the orientation - but again throwing the balance out - choices! If I could just rotate the camera it would be easier to frame targets and allow better balance.
  6. Nice image, the PS tricks worked well Unfortunately, I need 60mm back focus + the width of an adapter and with no dedicated reducer I'm wondering if the Esprit 120 is going to do the job.
  7. I assumed that if you got good focus using a mask that the backfocus must be ok. From what you are saying it sounds like you also need to adjust backfocus within the "in-focus" range. Is that correct? Presumably you are talking fine adjustment with Delrin spacers or similar?
  8. I looked at the SW pillar mount last year, for a different reason but got warned off by a few people who reckoned the tripod was a much firmer base. Always hard to know with these things without trying or getting good references.
  9. I leave the rig set up but have to move it outside each session. I'm thinking of having 3 x 3 wheels "coasters", one under each leg so I can wheel it out and then one leg at a time remove the coasters. Also looking at full dolly's but they are expensive and its something else to wobble I think the backfocus issue comes from the flattener used, the straight SW flattener gives 75mm which is fine. I haven't identified a reducer yet, seen people discuss Riccardi, Hotech etc but the ones I looked at so far only have 55mm BF so looks like they are aimed at DSLR users.
  10. Just trying to understand where the limitations are. For example if the guiding isn't limited by the seeing it may be worth me buying a Stellar Tuned EQ6 from the outset rather than an out of the factory one and then maybe later wanting to get it tuned? I need to check that RMS figure, I'm sure that's what I was seeing but it does sound too good.
  11. Based on the 100 and 150 do you think the 120 will go on an EQ6R-Pro without crashing the tripod legs - just read a post that suggested this combination may prevent meridian flips and zenith imaging?
  12. I would be interested to know which camera you used for these images?
  13. The thing is (aargh!) the HEQ5 limitation severely restricted the scopes I could use - now I'm considering an EQ6 I have even more options That said I do think the Esprit 120 would be good, I'm so pleased with my 80. As I mentioned above, the only issue with the 80 was the short back focus on the flattener so I'm trying to see if its the same with the 120. I would REALLY like a manual camera rotator in the image chain but no chance with the 80. I know you can rotate from the focuser but it changes the balance and unless the FW was vertically up or down it would never balance the same on both sides of the pier. I notice it more since the Stellar tune as the mount now rotates so freely the slightest misbalance is noticeable.
  14. Stretching my knowledge now but does that mean if the scopes diffraction limit is less than the seeing limit - as in 1.5" is less than 2" seeing - the seeing dictates what is possible and the scope doesn't have any influence. I will probably also use a reducer so if the diffraction limit is based on focal length it would be less than 1.5" at say 600mm (840mm native)?
  15. So much to consider So, is seeing going to have a much bigger impact with a 120 than an 80 - is it the aperture or focal length that influences it? Just wondering because the reason I am looking to upgrade is to get more detail in my images (and allow me to get smaller targets). My pixel scale with existing SX814 and 120 would be 0.91"/px which I think is ok for 2"-4"FWHM seeing.
  16. I am as we speak looking more closely at an Esprit 120 and EQ6R-Pro set up I haven't looked at mounts recently, does this mount seem like a reasonable way forwards - just looked at Mesu and they are out of my price range? From what Olly was saying I'm now thinking the mount doesn't need to be perfect, just better than the seeing. For info, I would like to continue using EQMOD, PHD2 and SG Pro. EDIT - Do you use a reducer on your Esprits, I cant see a dedicated one for the 120, just a flattener? The only issue I have with my esprit is getting back focus - my EFW/OAG/CCD takes 60mm.
  17. Thinking of getting one of these mounts but not sure it will fit in my HEQ5 cabinet. Does anyone have dimensions, ideally the ranges for the spread of the legs and height. Also, does anyone use a dolly with one of these - I wouldn't be able to lift it once the scope is mounted.
  18. Thanks for checking it. I'm pretty sure that when I was actually imaging it was showing an RMS of 0.21, I took a screen shot at the time but cant find it - also it may not have been the same night as this log. I use OAG with Lodestar so the guide scope is the esprit. The Dec drift is beyond my understanding, I generally do 20 min exposures for NB without problem, this was just a test when I got the mount back, it's not run in yet so may settle down.
  19. There are some very nice images there and generally star shapes are great - although oddly some of them show quite a bit of star stretching in the corners with an ASI1600 - presumably more so if it were full frame. I'm being picky though, I would be please to be imaging at that standard
  20. Thanks Olly, great advice as always. I'll take a look at the TEC 140 but where do you pick these things up, I've been looking on SGL and Astro Buy Sell for various scopes fro a while and not seen much? I can be slow on the uptake but your "supernaturally good" comment alerted me to a high probability of a cock-up on my part 😮. TBH I'm still at the stage where I know what to do but don't always understand "why" in detail - including guiding so "mia culpa". I thought I had the RMS set to arc" but I'm wondering if I was looking at pixels - sample log attached (see entries 8 through 11 - everything else was calibration and Guide Assistant). I would be grateful if you would take a look and let me know what you think. Whilst imaging it was showing around 0.21 RMS but I suspect dithering must throw this out (?). The HEQ5 has just come back from Stellar tuning so this is a first run, its not run in yet but hopefully will improve and should last quite a while - I think all the bearings have been replaced. Compared with pre-tuning its massively improved, I can leave it to run for hours whereas before I would be constantly tweaking it. Thanks again Olly. PHD2_GuideLog_2020-04-11_203434.txt
  21. That's a good point and something I was conscious of while reviewing images on Astrobin. Whilst a lot can be done in processing, and I am currently spending a lot of time learning PI (a benefit of the lockdown!), I still want the best raw ingredients I can produce
  22. Interesting idea but I buy a car for comfort. For astro equipment its all about the quality of the image, I dont care what it looks like or who's name is in it 😛 Just wondering if the issues I have seen in the images I have been reviewing are as much to do with how those setups were calibrated as the quality of scopes. I guess a lot of people, myself included, are not experts when it comes to tuning sets ups, adjusting tilt etc.
  23. Pretty much. I will look at each sub and say, could it be better? What could I do to make it better? But I will also ask was it worth the extra £? My budget was around £2500 to start with, I then started looking at the TSA-120 and APM 115 LZOS (around double when the extras are included) expecting to see a significant improvement in image quality. I haven't costed a 106Q but I'm guessing it will be at least £6.5k with a flattener adapters - I could just buy it but if I survive longer than I'm expecting I might have no where to live :0 Also, I'm really looking for a longer FL - be interesting to see some full frame images with stars as good as yours taken with a TSA-120.
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