Joined: Sat May 18, 2013 12:20 pm Posts: 37 Location: Africa, Europe, America, Middle East
Hi everyone,
I just bought a 30x "Jeweler" 6 White LEDs + 1 UV LED loupe from Hong Kong. I purchased it via eBay. I wish to share my impression with you.
I still don't carry a microscope with me in the field. And until I pull the trigger on a Krüss KA52KRS, I was looking for a portable inexpensive solution. So I order this loupe :
For sure I wasn't hoping to get the optic qualities of a Krüss Weinschenk 10x-20x-28x. But I was expecting at least a real achromatic and aplanatic lens like advertised in the product description. Well the lens is indeed achromatic but it's NOT aplanatic at all! I played more than an hour with my loupe. Trying all different distance from my eye and/or from the object. There's nothing I could do. A lot of spherical aberration! And I do have very good vision, I have a 20/15 vision which is better the normal 20/20 visual acuity.
I took these picture below with my cel phone, the focal distance is not right, but believe me, when I put my eye close to the loupe, this the kind of spherical aberrations I see. It's just so you can understand what kind of huge spherical aberrations I'm talking about.
About the LEDs...
The UV LED is so dim that it's useless. The 6 White LEDs are bright enough, but oddly, probably a design flaw, you can see a lot of reflection in the lens. I didn't have that problem with the Krüss LED 10x loupe - LUK 10/20 http://www.kruess.de/shop/advanced_sear ... 1&x=4&y=13 Although I do have an electrical problem with the Krüss : Subject: NEW Krüss LED 10x Triplet Loupe: Electrical problem The US retailer I bought my Krüss LED loupe from is still waiting a reply from Krüss technical support about my electrical problem with the loupe. I don't know what those guys in Germany are doing, they're soooo sloooowww to come with an answer! Krüss do manufacture great product, but they really need to a work on improving their customer service (before and after the sell). UPDATE: Mid-June... Kruss sent a whole new batch of loupes to the US retailer and they're all defective! Unbelievable! So when ordering one, you should ask the seller to test the loupe before he ships it to you.
Back to the 30x "Jeweler" LED loupe from eBay... It's not because it's from China that a product is automatically cheap and crappy. I mean my 27-inch iMac, 13" MBP, iPad, iPhone, iPod are all working perfectly! So from the product description on seller's eBay web page I though I was making a good deal. I was wrong.
Verdict: Maybe good enough for coins or stamps, I don't know, but I surely cannot recommend this 30x LED loupe as a jeweler loupe.
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Fri Jun 21, 2013 1:25 pm
Established Member
Joined: Sat May 18, 2013 12:20 pm Posts: 37 Location: Africa, Europe, America, Middle East
A note about the eBay seller "discount_instrument" I bought the loupe from.
Although the item is not as described I'm willing to give this eBay seller the benefit of the doubt. The loupe manufacturer provides product specs sheet and the seller uses this info in his ad. This does not exempt the seller from liability to announce its product properly with the exact specifications. But at least this seller did everything to resolve my dissatisfaction. He had an excellent communication and after sale service. It was really easy to communicate with this seller via emails. He was very quick to answer and very helpful to resolve the communication. I felt that this seller did emphasize on customer satisfaction.
Like I wrote in my initial post, I cannot recommend that 30x LED loupe if you're a jeweler. But if you're willing to give a try maybe at his 10x LED loupe (the 10x model might has less noticeable spherical aberration) at least know that if you're not satisfied with the product I do think this seller will do everything possible to resolve the situation at your satisfaction like he did with me.
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Sat Jun 22, 2013 7:05 am
Valued Contributor
Joined: Tue Nov 01, 2005 7:30 am Posts: 203 Location: London
Barbra, I have been using one of these darkfield loupes for years and they are a valuable tool. I use it 'in the field' and look at just about everything I buy through this loupe.
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Sat Jun 22, 2013 1:16 pm
Platinum Member
Joined: Tue Jan 02, 2007 8:20 pm Posts: 2659
Just an informational point. Anybody who offers you a 30x loupe is probably offering a product that was labeled fraudulently , somewhere. Perhaps farther back in the production/supply chain.
I have a Bausch and Lomb 20x Hastings Triplet. It actually is 20x and is not easy to use. Very close working distance. Focal length: about one half inch (12.5mm)
The working distance on a 30x would be proportionally less. Focal length: One third inch, 8.33mm
30x is an amount of magnification that really justifies a microscope. (ie.3x objective and 10x ocular, a combination you see all the time [the searcher lens] even on a compound [Dr.s] microscope.) A loupe is a cousin to a microscope ocular. 10x , 15X and 20x are common in that area. But 25x, 30x, 32x and 33x while occasionally offered and seen, are really not widely used because 1) they are VERY expensive and 2) even on a microscope they suffer from bad usability problems.
In 45 years of carefully watching the offerings of companies who make loupes I have NEVER seen any legitimate big name optical firm try to manufacture and sell a 30x loupe. They care too much about their reputations. The 30x loupe has strictly been the province of noname far east manufacturer's. I have lots of stuff from there and even like some of it, but a 30x loupe is something everyone should run in the opposite direction from. If someone wanted to build a real 30x loupe it would need to be optically complex and expensive. I have simulated such things using a microscope tube and a 2x or 3x objective and a 10x or 15x ocular. Not really worth using. (Bausch and Lomb made some "Macroscopes" like that once upon a time. Did not sell well. But they weren't single lens loupes.) They might have been more fun with an LED ring lighting system.
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Sat Jun 22, 2013 2:27 pm
Active Member
Joined: Sat Feb 23, 2008 8:18 am Posts: 71
Quote:
I have a Bausch and Lomb 20x Hastings Triplet. It actually is 20x and is not easy to use. Very close working distance. Focal length: about one half inch (12.5mm)
for any thing over 14x its better to use a microscope i also tried the 20x bausch and lomb i found it very hard to use now i just use the 14x
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Sat Jun 22, 2013 7:17 pm
Established Member
Joined: Sat May 18, 2013 12:20 pm Posts: 37 Location: Africa, Europe, America, Middle East
After reading your good reviews of BelOmo loupes I ordered their 20x Quadruplet loupe. I'm really happy with it so far: robust construction, good optics, good usability.
I then did compare the 20x BelOmo versus the Chinese 30x. The BelOmo has greater magnification! If the BelOmo is really 20x (not higher) well the Chinese 30x is more like 15x-18x That tshinloupe has really some tshinspecs...
My BelOmo came with lint (or dust from manufacturing?) on the lens. But I couldn't take it off. I finally found out that it was INSIDE the lens. So I took the loupe apart to clean it. It uses two dual (or duplet) lens in opposite configuration with few millimetres apart from each other.
Note: The black ring at the top left of the two lens is the spacer holding the two lens few mm apart from each other.
Ms Voltaire, about your darkfield 10x loupe, is the lens fully achromatically and aplanatically corrected?
I bought the Krüss darkfield 10x loupe at a much higher price because the Krüss sales rep told me that the lens, as for all Krüss loupes, is made in Germany by a german supplier. But I'm not sure if Krüss told me the truth...
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Sat Jun 22, 2013 11:47 pm
Site Admin
Joined: Sun Oct 16, 2005 12:22 pm Posts: 21602 Location: San Francisco
DavinciQc wrote:
about your darkfield 10x loupe, is the lens fully achromatically and aplanatically corrected?
Yes. A Bausch and Lomb 14X Hastings Triplet was the first one I ever bought for myself when I was in college. I still have it attached to my key chain for emergencies.
For work, I use a 10X GemologyPro by Schneider for initial inspections and then go to a scope for fine tuning.
Belomo is a good option for those on a budget. The screws on the Belomo used to be unreliable, but they've fixed the issue I'm told.
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Sun Jun 23, 2013 1:35 am
Established Member
Joined: Sat May 18, 2013 12:20 pm Posts: 37 Location: Africa, Europe, America, Middle East
Barbra Voltaire wrote:
Belomo is a good option for those on a budget. The screws on the Belomo used to be unreliable, but they've fixed the issue I'm told.
Yes I agree for the price the BelOmo 20x loupe is very good buy. I do prefer the clarity of my Krüss LED 10x, but it costs 4 times the BelOmo. And Krüss does not manufacture a LED 20x loupe yet...
About the screws on the BelOmo. When I took apart the loupe I saw a solidified substance around the screws that looked like a kind of Loctite. So they kind of solved the issue. But sadly this solution only works until you need to take apart your loupe to clean it, as I had to do. Because then you'll need to have Loctite on hand to apply some yourself.
Post subject: Re: 30x Jeweler White + UV LED loupe
Posted: Sun Jun 23, 2013 1:38 pm
Platinum Member
Joined: Tue Jan 02, 2007 8:20 pm Posts: 2659
A dot of super glue works about as well as Loctite. Especially in the application to a loupe which is very low stress on the screws. Both are acrylics although they are quite different acrylics.
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