mcbras

I appreciate your feedback. Will start with collimation and going from there. Greets

Hello everyone, I attached an image that came straight out of the camera. I have half of image with ok round stars and half of it with enlongated stars. I feel that either is poor collimation or the focuser is sagging a bit.. Images are 600s exposure with guiding. I recently did a polar alignment and the same day I took this image, I realigned the guiding scope with the main scope. Anyone that had similiar issues or knows what it is, has any suggestion to make in regards to this matter? Thank you so much Miguel F8300_IC1396_LIGHT_O_600s_BIN1_-10C_001_20220918_212530_634_PA148_W.FIT

Hi, as a follow up on this issue, may others take advantage of it, seems like my mirror cell wasn't tight enough so I was getting those lines in there. I still have to do a final testing, but weather in this northern europe countries really present themselves a challenge for astrophotographers, geez! 😬

vlaiv, thank you for your thoroughly explanation. In the place I'm at, no power lines close by, not even if I image close to the horizon, so I can put that aside, along with the anti-blooming, unless something is wrong with the camera. I did a primary cleaning followed by a collimation a few days ago, so I'll check if the mirror is well secured. The funny thing, though, is that I took 4h of frames with same filters in M33 before this sequence and nothing like that showed up on camera. Only difference is that my guiding was really terrible for this target in Dec (I still fight with my NEQ6-Pro to get good Dec, even though I can get 0.5 RMS most nights). I will for sure image this target and play with different exposures to see what else is to become the next challenge (there's always one in this hobby) to be solved. Once again, thanks for the valuable info. Best Miguel

Gents, yesterday I was testing a diy dewheater band and I took the chance to image something. I pointed the setup to the horse head nebula, after doing M33 with success, and every single frame is kind of like this, in LRGB. The ones in here are in Lum 120s exposure. Should I reduce the exposure time in order not to saturate the adjacent pixels? Why it only happens in the short image direction? The setup is a fast reflector with coma corrector along with an Apogee Astra 8300 CCD. Thanks for any possible inputs. NGC_2024_LIGHT_Lum_120s_BIN1_-15C_002_20201113_050723_642_PA29439_E_F41715.FIT NGC_2024_LIGHT_Lum_120s_BIN1_-15C_003_20201113_035152_301_PA29439_E_F41825.FIT

Hello, I like doing astrophotography and I've put an order for a rotator that has 18mm of back focus. Right now, in my 8'' reflector along with the image train, the focuser is around 12mm sticking out from the most inner position, on average, for the CCD to reach focus. If I'm thinking things correctly, I know I won't be in focus by 6mm. So, looking down to my mirror cell, I wonder if I can push the focal point 10-15mm out in the focuser area if I just use some 10-15mm spacers in between the spring and mirror hold bolts. Does this makes sense? I'm not in the mood of cutting down the OTA the same distance. Anyone tried such thing? I'm pretty much sure that the actual mirror holding aparatus can be separated from the rest of the cell that screws in the sides of the OTA. Thanks!

Hi, I don't know why but I'm getting the most ugly stars I ever seen. I do guided subs and PHD2 doesn't report big error, and I'm actually assuming that this can be due to anything, but would like to hear from you what are the most probable causes for this. My rig is a 8'' newton with an RCC I baader coma corrector, apogee FW and CCD on top of a NEQ-6. My guiding telescope is Skywatcher Evoguide 50ED. Below you can see one sub that I just saved as TIFF from FITS Liberator. I appreciate if anyone can guide me to possible solutions, what to look for, any tools to help , anything, because I never seen any of this on other users reports, here or in other forums. Thanks MB 2020-06-20_300sec_1x1_lum_-15C_0300_fpos_20131_0002.tif

Mark, thanks for the reply. Due to the current setup, I will abandon the rotator idea. Now, I need to do my custom piece, nose piece type to attach my Baader RCC I corrector (M42) on the telescope side and to attach an Apogee AFW 50 9R on the camera side (2''24 thread). Ran the math and I arrive at 37.2mm. First, I guess I will keep like 1 or 2 mm shorter to have room to fine tune it if needed. Anyone sees issues with it? Went to preciseparts.com and although they have the equipment listed, the final prototype is so huge that i can´t the part in a 2'' focuser tube. Any idea how I can connect the above-mentioned items with a single custom piece? ´Thanks!

Hello, after reading so much stuff about backfocus, I get confused when it comes to realize what I have to do to make my setup work. Can somebody please validate my thinking: Equipment: OTA GSO 8'' 800mm focal length (f/4) Baader coma corrector RCC I with 94.5mm back focus FW AFW-90R from Apogee with 29.2 mm thick but I consider 28.2mm due to filter in there CCD Apogee Altair F8300 with back focal distance of 26mm Now, the setup it's still not working, I keep getting coma, but I understand why. If the light out of the corrector will be in focus 94.5mm behind it, I need to add a 40.3mm extension. This makes sense, correct? But now, I'm looking to add a rotator, in this case a OPTEC PYXIS 2-INCH GEN3 which takes 41mm of focus. I really don't see if this will work or not, because I'm assuming the rotator it's simply a tube that will have the whole optical train attached and will rotate under a certain axis. Can you please clarify me on that? Thank you so much!!