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Everything posted by michael.h.f.wilkinson
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New 40mm Lunt solar scope
michael.h.f.wilkinson replied to Nigella Bryant's topic in Discussions - Scopes / Whole setups
Upgraded LS35 by the look of it -
Need some ep advice
michael.h.f.wilkinson replied to Shaun Sr's topic in Getting Started Equipment Help and Advice
Some good suggestions already given, and of course ideally you might want ALL of them . The 40 mm Plössl that comes with the EdgeHD is a 1.25"type which is not ideal, but a 2" 40 mm wide-field EP can be great fun. The Delos 10 is a definite keeper, I would say. I have a Pentax XW 10mm in its place, but that was because the Delos didn't exist when I bought the XW10. I do have an 8mm Delos to sit between the XW 7mm and the XW 10mm, and it sees a lot of use on planets. The 14mm Delos replaced a Morpheus 14mm I did own, but didn't get on with due to some field curvature in the outer field. I hear the 14mm is the weakest in this respect in that series, the others are reported to be excellent and great value for money. I used to have a 40mm TMB Paragon (the TS Paragon and SW Aero are clones) was excellent for wide field viewing in my Celestron C8, once I got a 2" visual back and diagonal. I foolishly sold it after getting a second-hand 31mm Nagler. I now have a 42mm Vixen LVW. I also have a range of ultra wide EPs between the 42 and 31 mm wide fields and planetary bunch at 22, 17, and 12 mm. This is really a densely packed range, but something like a super wide 40 mm or ultra-wide 30-24mm would be handy for exploring larger DSOs, something intermediate at 14-17mm for smaller DSOs, and at a later stage perhaps something like a 6-8 mm for extra planetary work at moments of good seeing would be useful. I would certainly go and look for second-hand offers, as you can make great savings, and if an EP somehow disapoints, you can sell it at little or no loss -
Superb image!
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Barlows are an economical way of increasing the number of magnifications at your disposal, and quality Barlows or tele-centric lenses like PowerMates or TeleExtenders do not compromise much in terms of quality, compared to the plastic horrors it has been my profound lack of pleasure looking through in the distant past. I still have some tele-centric lenses, but use these mainly for planetary, lunar and solar imaging. For observing I much prefer having a range of individual EPs, not so much because of optical quality, but due to ergonomics. Especially for planets, I really like to switch directly between EPs (preferably parfocal ones too) so I do not lose critical focus, or only have to adjust minimally. Switching Barlows as well often moves the plane of focus significantly, which might mean missing brief moments of good seeing. Combining a zoom lens with a Barlow might actually work a bit better in that respect, allowing you to choose a suitable range (e.g. 4-12 or 8-24 mm) depending on the target, by choosing whether or not to use a Barlow.
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Is this an upgrade?
michael.h.f.wilkinson replied to Back40's topic in Discussions - Scopes / Whole setups
My Celestron C8 sits very nicely on an EQ mount, and has done so for decades, so I can see why you would like it. I have looked through a 10" Meade SCT and was rather shocked at the bad image, thought this couldn't be right, defocused the scope and spotted it was WAY off collimation. With proper collimation it should be a step up from the C8. I have a Meade Schmidt-Newtonian myself which is fine, so Meade can do good optics. The CGEM-DX is a pretty solid mount by all accounts -
For me, 3:15 was near optimal, and I did manage to find it, but that translates to 2:15 or a bit later UK time. At 3:30 it was getting a bit light already and the comet looked paler. I would guess 4:15 here would be close to the time you observed, and the comet was definitely not visible here anymore
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Manage to capture comet C/2020 F3 (NEOWISE) in the early hours. First needed to dodge some clouds, but later they moved off, allowing me to capture a series of 37 shots with the 200 mm F/2.8, which I stacked in AS!3 and cropped and stretched in GIMP. Quite pleased with this first naked eye comet in 24 years. and with comet number 29 in total.
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Reflector vs Refractors
michael.h.f.wilkinson replied to Dannomiss's topic in Getting Started Equipment Help and Advice
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Faster Scope for imaging
michael.h.f.wilkinson replied to carastro's topic in Discussions - Scopes / Whole setups
The 80 mm F/6 with 0.8x reducer is actually faster (F/4.8, or some 60% more light for a given exposure time) at nearly the same focal length (384mm), and you have a 480mm as well. Besides, in my experience you almost always need to stop a camera lens down to get good stars in the corners -
How do I get a sharp image of the moon?
michael.h.f.wilkinson replied to JTTW's topic in Getting Started With Imaging
Try using a Bahtinov mask on a bright star, to get exact focus with the ASI224MC, and then go to the moon. The difference in focal position for the moon or a star is in the order of a nanometer, so far less than the wavelength of visible light, and makes no difference. -
Faster Scope for imaging
michael.h.f.wilkinson replied to carastro's topic in Discussions - Scopes / Whole setups
I think their focuser has the usual mounting point for a Baader finder shoe, so the finder guider should fit. You can also attach a guider to the top of the rings (there are threaded holes visible in the photo). I remember their initial 65 mm quadruplet flat-field had some issues with pinched optics, but I believe they have been sorted in the later versions. I have a similar 80mm F/6 triplet to @vlaiv's one, and use that with either a TS 1x flattener, a TV TRF2008 0.8x reducer, and did some experiments with a 0.6x reducer. This gives me multiple options in terms of speed and FOV. I can't fault the scope, either for solar or DSO imaging, or for wide field observing -
Astro Pixel Processor (APP) does that very easily. I have combined shots of M33 with the EOS 550D and ASI183MC before, no problem. In APP I either use the multi-session option and stack the lot, or (much easier I find) I let APP compute a weight map for each stack from the individual sessions/instruments, and then stack the stacked linear results with the weight maps loaded. Works fine.
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TS Planetary HR vs Vixen SLV
michael.h.f.wilkinson replied to Ags's topic in Discussions - Eyepieces
That report was done at 375x, so seeing probably limited performance. I have the 4mm SW Planetary as part of a set of EPs for my kids' mini-Dobson. I have used it in my 80 mm F/6 triplet, where it performed nicely, but I prefer the views through the 5mm SLV (different magnification however). -
NLC display now 23:30 30/06
michael.h.f.wilkinson replied to Ant's topic in Celestial Events Heads Up
Clouds and rain here, and it looks like they are camping here for the coming week -
TS Planetary HR vs Vixen SLV
michael.h.f.wilkinson replied to Ags's topic in Discussions - Eyepieces
I think the brain interprets a blue or neutral tone as brighter than a slight brownish cast, that would explain your observation. I have seen that effect when designing and setting up stage lighting (as a student). Using using the equivalent of an 80B filter turning the quartz halogen light into daylight, always seemed to make the stage look brighter than if you used salmon or gold filters. -
Pentax and Delos 3.5mm eyepieces
michael.h.f.wilkinson replied to alan potts's topic in Member Equipment Reviews
Unless you buy second-hand and take care of the kit. In that case you often sell at nearly the same price you orginally bought it for -
TS Planetary HR vs Vixen SLV
michael.h.f.wilkinson replied to Ags's topic in Discussions - Eyepieces
Colour tone can be corrected by the coatings, of course at the expense of transmission. I really didn't notice any colour tone in either the XWs or the SLVs. I did notice it in the Radian 8 and 10 mm EPs I used to have, but it didn't really bother me -
Jupiter & Saturn 24th 6 2020
michael.h.f.wilkinson replied to si@nite's topic in Imaging - Planetary
Very nice images, especially with the planets so low in the sky -
Pentax and Delos 3.5mm eyepieces
michael.h.f.wilkinson replied to alan potts's topic in Member Equipment Reviews
The Delos 6 mm and 8 mm focus 1/4" further out with respect to the XWs, the 14 mm slightly further in, which means the 6 and 8 can be combined with parfocaliser rings to make them parfocal with the XWs, but not the 14. -
catadioptric OTA mirror obstruction
michael.h.f.wilkinson replied to bomberbaz's topic in Discussions - Scopes / Whole setups
It was a 6" F/8. -
THE RAPID BRIGHTENING OF COMET NEOWISE
michael.h.f.wilkinson replied to paulastro's topic in Celestial Events Heads Up
Very interesting. Fingers crossed for some clear skies around July 10 and beyond