I think the lever is maybe slightly bent and due to some friction it gets stuck. How does it feel when moving it manually? Also, maybe a silly question but worth asking. Is your diaphragm oily? Best

@diyextravaganza not really oily. It doesn't take a hard push, when I slightly touch the lever it goes back. But it still anointing me because I have to take the lens off the camera.

@tarask9971 remove the black plastic element and try without, let's debug element by element.

@@philippe6743 you're welcome, please share with friends.

Il y a des gens qui les trouvent utiles. On trouve facilement des pièces de rechange sur des sites internet, on peut fabriquer ses pièces aussi, j'ai déjà fait des pièces de rechange en impression 3d. Salutations.

@@diyextravaganza ( On trouve facilement des pièces de rechange sur des sites internet, ) faut ! si s'est si facile que ça ! mes des lien ! ( j'ai déjà fait des pièces de rechange en impression 3d. ) oui des par soleil en plastique ! se genre de truc que tu trouve tout fait sur .thingiverse.! entre autre mais les pièces électronique !! tintin

@@markgoostree6334 I'll try that when I have the opportunity. Thanks for the advice.

Is it easy to find?

@@petitgrisgris9545 cela se trouve sur le net, sinon un objectif en mauvais état ayant la pièce d'intérêt.

@@Andy-rk9mu to be honest, I didn't think about that option, but it is an idea worth trying and will try it next time I get a sticky camera. Thanks for the suggestion.

Many thanks!

Don't forget to share with friends :)

@@julianrobertson3303 you're welcome my friend. Please share with others. Wishing you good repairs.

@@diyextravaganza I will share with others for sure . Thank you .

It is different, I've never done a video on this, I don't think I have one of those around for repair, if I get one, I'll think about making a video. Regards.

Hola, es un resorte de tension, se consiguen en muchas partes, en tu país seguramente encontraras, hay solo que medir el tamaño aproximado en la bayoneta, y asi encontraras facilmente. Yo debo tener alguno disponible que te mandaría con placer, pero el correo va a salir más caro que el resorte.

You're welcome, it's a fairly simple process but take care when reassembling, especially with the ribbon cables.

4 water, 1 part alcohol. Or 20% of the total preparation is isopropyl alcohol. Regards.

@@diyextravaganza Thank you!

De nada, compártelo con tus amigos fotógrafos. Saludos.

@@classic.cameras it's a good idea. Will do.

Great. Don't forget to share with friends!

En muy mal estado se encuentran baratos, a ver en mercados de pulgas. Saludos.

@@christophewagner4028 et tu as bien raison, le 105mm f/2.5 est un objectif excellent. J'ai reçu un Zeiss 100 f/2 Aujourd'hui, il semble intéressant. Salutations.

depende de que tan facil sea acceder al hongo. Saludos.

Smart girl, and I hope she'll be smarter than her dad. 😉

You're welcome, I find this simple method far effective than Lens vise tools. Don't forget to share with friends.

Hello, I can take your lenses if you want. Write to me to [email protected] so we can discuss the details. Regards.

probablemente no sea posible pues la distancia minima entre la ultima lente y el sensor es fija, todo cambio en ella implica que no puedas hacer el foco al infinito. Al menos que sea una camara sin espejo, en cual caso solo necesitas un adaptador sony a nikon Z. Saludos.

@ muchas gracias

@@blackimp4987 I made sure the white balance was identical in both images. So, yes, it's the lenses color rendition. Regards.

@@blackimp4987 Hi, nothing is impossible, but my guess is that it would be a custom part as I doubt the newer version is a 1 to 1 replacement. Cheers.

@@diyextravaganza thank you. I made a mistake anyway. AIS version does have 9 blades but they are less curve anyway. If you ever open a newer model and you realize it's possible it would be amazing if you could tell us. Maybe with a new video. Thank you again

@blackimp4987 you're welcome. If I ever have the opportunity to open one, absolutely.

That's great news. Thanks for the feedback, don't forget to share my channel with others so they can also find help. Regards.

J'ai un deuxième summicron, ja vais faire des images comparatives.

@@diyextravaganza tu peux avoir de la chance aussi ... mais je sais de source sûre que le calage du foyer optique a une très grande importance sur des optiques de cette classe ...

@@pascalszwzeiij1194 le test comparatif nous le dira, au pire, j'apprendrai à régler des summicrons. Salutations.

The connection of the ribbon cables must be checked. Regards.

Ok thanks, will try that 👍

@@alexced3923 hola, desarmaste la parte de foco o solo la parte óptica? Si solo la óptica, si, de pronto pusiste una lente al revés (ya me ha pasado), si es la parte de foco, te quedó mal alineado. Saludos.

@@diyextravaganza Desarmé los dos lentes grandes de arriba y dos chiquitos del centro. Volví a la tediosa tarea de desarmar-armar y parece q se arregló lo de la inversión del foco. Una duda: no me fijé...pero ¿ lo convexo de los dos lenrtes grandes va hacia afuera los dos? Todavía se ve borroso, pero menos. Este lente es muy bueno...bastante "sharp". Ojalá un día puedas desasrmarlo. están bien bien baratos en ebay.

@@zeuzsanchezlira-tq7wj normalmente se puede. Utilizar un paño microfibra. Por seguridad, ensaya antes en una "esquina" antes de proceder en toda la superficie. Saludos.

@ gracias por responder 🫶🏽

I don't think there is a way to know that easily, on the other hand, the list of options is short. Canada balsam has been used for a long time, synthetic glues are more recent I'd say. The Mamiya is not a recent lens, so, I'll bet for the canada balsam. Before actually separating, heat at about 100°C and press both elements together, if the separation is not severe, that should work. Regards.

@@diyextravaganza hey thank you for your reply. I didn't quite understand the last part. do you mean the haze could be result of separation and maybe if I heat it and press it together it will go away and I don't need to completely separate the elements? The elements look very solid from the outside at least. As I was searching on ebay to see if I can find one for parts, I saw a lot of them with the same issue. Is it possible that it's the cement (canada balsam or any other) used in these series that develops this problem? I live in germany and it's possible that previous owner has stored the lens in cold and humid basement for a long time.

@ariansadafi4033 yes, sometimes the haze is due to the cement degrading over time. If it looks hazy, most probably you'll need to fully separate. The heating and pressing works for the separation that looks like rings (Newton rings)

@ thank you very much! Just one more question! After heating it up to 200-210 degrees is it safe to take out the lens out to room temperature? I’ll try to test it next week and will let you know if I could do it on the first and only try! 🙂

si, ya me ha pasado, con un Nikon 35-70 f/2.8 como el de este video kzbin.info/www/bejne/jWnVYYmcedF9odU el resultado es interesante.

Was it like that when you got it, have you disassembled it? Best

​@@diyextravaganza It was like that when I got it. The previous owner must have tried to open the front side, because there are some scuffs. I suspect that some of the elements are placed backwards... or missing. Everything else works. AF, switches...

​@@diyextravaganzaIt autofocuses on extreme close up, only. It won't turn the screw from maybe 20-30cm and further. It's just buzzing. It also gives the wrong distance at close up.

@@mladen5016 ok, so, it seems the lens was disassembled and reassembled wrong. Once bought one of these disassembled because owner was not able to put it back together.

​@@diyextravaganzaThank you.

@@ctdrone you're totally right, also proof that at the end of the day the camera is irrelevant, what matters is what you put in front and behind of it. Don't hesitate to share with friends.

@@antiplouc is a squeaking or rather a rattling sound? Does the focusing has hard points? Best.

@@diyextravaganza no hard points but hissing and squeaking. It doesn't stop me to focus but it can be heard when i shoot a video.

@antiplouc I think a regrease shall improve that, but these lenses have a gear mechanism so noise won't go entirely.

@@diyextravaganza Do you have a video that shows how to do that?

Tiene un anillo para desatornillar? Si es el caso, ponle una gota de acetona para aflojar trazas de pegamento. Saludos.

You're welcome my friend. Please share with friends. 😊

Cela arrive des fois, vous pouvez essayer en mettant une goûte d'acétone afin de rémolir des eventuelles traces de colle et attendre quelques minutes avant d'essayer. Operation à répéter si besoin. Salutations.

@diyextravaganza Merci beaucoup pour votre retour rapide

gracias mi amigo, un muy buen lente este. Saludos.

@diyextravaganza lo tengo en una Nikon F-501

@@arielgajda3335 excelente camara

Por nada mi amigo !

@@yummygogolak thanks for the advice.

@@ThirdEye105 thanks for your insights, they are greatly appreciated.

@@jean-luccourtois7766 bien au plaisir mon ami, je te souhaite beaucoup de belles images avec cet objectif et ton D700. Et comme toujours, n'hésites pas à poser des questions si besoin.

@@RookieNeko lo mejor es retirarlo y limpiarlo. Sería necesario abrir la cámara para efectuar la reparación. Saludos.

@@alexced3923 I tested this particular copy on a Nikon d810A and I was surprised of the results. Trees far away looked sharp.

@@diyextravaganza thanks.

Gracias amigo, los 50mm son la gran mayoría de diseño similar. De pronto te vas a encontrar con un grupo óptico sellado, pero en el canal explico en un vídeo como proceder. Saludos.

@@WILMORENO you're welcome my friend.

@@christianbumatay yes, it is full frame. In fact near every lens from the film era is indeed full frame.