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主題: Askar 的 PHQ vs FRA 的產品線定位怎麼區分 下圖2隻相近的鏡子 各位又會怎麼選擇呢 作者: peter 於 2024-02-22 08:43:48 Askar 的 PHQ vs FRA 的產品線定位怎麼區分
下圖2隻相近的鏡子 各位又會怎麼選擇呢 https://www.facebook.com/photo/?fbid=7294128140668006&set=gm.3669737979965239&idorvanity=1782041272068262 主題: 回覆： Askar 的 PHQ vs FRA 的產品線定位怎麼區分 下圖2隻相近的鏡子 各位又會怎麼選擇呢 作者: peter 於 2024-02-22 08:45:20 https://www.cloudynights.com/topic/856662-askar-frp-and-phq-what-is-the-difference/
FRA are faster. PHQ are slower. So the 65mm phq is slower (but longer focal length) than the 300 FRA. The longer, slower telescopes are easier to make in terms of optical quality, so basically the phq 65 is slower and longer and the FRA is shorter and faster. 主題: 回覆： Askar 的 PHQ vs FRA 的產品線定位怎麼區分 下圖2隻相近的鏡子 各位又會怎麼選擇呢 作者: peter 於 2025-12-15 11:28:12 https://familystar.org.tw/index.php?option=com_smf&Itemid=4&topic=39712.new
(https://familystar.org.tw/forum/index.php?action=dlattach;topic=39712.0;attach=235136;image) https://www.cloudynights.com/forums/topic/958892-difference-between-askar-sqa-phq-fra-apo/ SQA Series SQA55 SQA70 SQA85 SQA106 PHQ Series 65PHQ 80PHQ 107PHQ 130PHQ 151PHQ FRA Series FRA300pro FRA400 FRA500 FRA600 APO Series 103APO 120APO 140APO 160APO 185APO 203APO FMA Series FMA135 FMA180pro FMA180 FMA230 SQA. Like Takahashi but cheaper and most likely no "lighthouse" aberrations. Pricey for the aperture. But apparently good. According to YouTube they are the new Redcats... Probably the best do it all. But price to FL ratio and aperture is the lowest while quality is the highest. But long focal lengths is not so much what they do. - PHQ. Slower focal ratio, so easier to get well controlled stars. Bonus points as they come in red and white with ZWO on the side. It sold me! Probably the best with longer integration/dark skies/price, trading speed for star shapes if you can accept the trade offs. - FRA. Fast(er) and with options (some). The 500 with a reducer is seriously fast. But probably worse stars than a PHQ. But speed is speed. And Blur Exterminator works. Best under polluted skies perhaps. -APO. Standard triplets, so unlike the above 3 "petzval, quad, quintuplets" means dealing with back focus. Not a big deal if it works out and you aren't bothered by that. The really big ones are probably to be avoided. The 103 and 120 are said to be amazing for the price. But you will be dealing with back focus. And lurid orange. - FMA. Ultra wide. Good and bad. More like camera lenses but trading better stars for focal ratio (speed). In seriousness, I have to hand it to Askar. In a few years they have come up with options for everyone. SharpStar HNT - Very fast hyperbolic newtonian reflectors SharpStar EDPH - Fast (reduced to faster than f/5), full frame traditional refractors. Askar PHQ - Slower Petzval refractors, full frame Askar FRA - Fast Petzval refractors, full frame Askar FMA - Fast wide field petzval refractors, APS-C and lens format design Askar APO - Very traditional triplet refactors. Full frame, requires a flattener/reducer and backspacing. Some very large designs available at a budget price Askar V - Flexible modular refractor Askar F - Budget friendly triplet petzval SharpStar Z - ??? A fast APS-C Petzval that makes no sense in the line up at all |